Very simple experiment: take a driver emitting at or above normal speech volume output (75dB and above) and let it play in free air. Then press the magnet (the heaviest therefore hardest to excite material of the driver) reasonable firmly on a number of surfaces including speaker cabinets, and listen for the difference. It’s there and it’s huge. Speaker cabinets are the single most important contributor to the sound signature once you are out of the treble range.
I found the B&W factory tour CZcams fascinating to realize the lengths they go to build a cabinet. The tweeter in a solid aluminum case and then on a rubber dampener to reduce vibration transfer from the midrange. So I then added a silicone dampener between my bass cabinet and the mid. Wow. Immediate impact to an already good sound. Clearer, less muddy. That is with cabinets made of 1.5" solid walnut.
Some speaker manufacturers make full range speakers that will reproduce 20 Hz accurately and with ease (if the amp is up to the job). And some of these manufacturers also make subs that are designed to work with their full range speakers. So why would a speaker, that can easily reproduce every frequency, benefit from a sub? (keeping in mind the goal is for accuracy -- not bloated double bass). The answer is to minimize the vibration in the main speakers. When you record video with your camera, you want the camera to remain perfectly still. When your speaker's drivers produce sound, you want them to remain perfectly still (and, yes, they move in order to produce sound -- I am talking about not moving from external forces). So by using a high-pass filter for the main speakers, and having the subs, in their own stand-alone cabinets, produce the most violent frequencies, then the main speaker cabinets will vibrate less, resulting in a better focused soundstage with better imaging, etc. Cheers!
In your example, there is more involved than just the cabinets. Since the woofers in full-range speakers usually work into the lower midrange, making them reproduce high-excursion low bass at the same time causes IM distortion of the midrange frequencies. This gets worse as sound level goes up. Offloading high-power low bass to a sub often yields audible improvement in midrange clarity. Then the only issue we have to contend with, is the same kind of IM distortion in our hearing. As far as I know, no one has been born with subears for those low frequencies.
Also, acoustic interaction in the room. Subs and speakers have different placement requirements. Oftentimes the ideal position for the Left or Right speaker isn't ideal for the subwoofer. Speakers are to be placed symmetrically, and subs placed according to minimize excitation of resonances. Rarely are those the same place.
When I build my house, it will be built from the ground up to minimize resonance. Nothing more annoying than the usual ~40hz room resonance...from the walls vibrating!
Great answer Paul. The clue is in the question, that's to say, resonance. All solid structures have a resonant frequency. If you introduce vibration they will vibrate too. However, the amplitude of the vibration will increase dramatically at the resonant frequency of the structure. It's the reason why bridge engineers have to make sure the resonant frequency of the structure is well away from the frequency of swaying caused by a strong wind, otherwise the bridge will tear itself to pieces. There is a famous video of just this effect. You can damp resonance by using a second material of a different size or density in close proximity to the the primary structure or you can go the stick on suppressor route. An example of the former is the platter on the Linn Sondek LP12. It has an inner platter and separate outer. The two parts have different resonant frequencies and one effectively damps the other. You only need a thin felt mat to support the record.
@@thekittencult I overcloaked mine with floor carpet tiles cut to size and glued to webbing. Very pleased with the result, now I can really hear the speakers clear and sharp !
This is Brian again. Paul, you nailed it. The cabinet resonance will definitely reverberate back into the output of the driver. Especially at high volumes. I believe speaker cabinet makers build their units to work at certain peak volume levels and extreme high volumes aren't a big consideration.
It's also significant that cabinet resonance follow driver motion in time and can extend for some considerable period of time after being excited. Additionally, the generally large surface area of a cabinet panel needs only to move a little bit to produce significant output. Thanks for a fine presentation, Paul!
That’s why it’s important to have a good ratio of weight to absolute stiffness. It’s not good to have something reasonably stiff but with a lot of mass. It will just blubber along anyway in the lower frequencies. Concrete can sing because it is actually not that stiff, but brittle and hard. Foam and foamboard are on the other hand not totally crazy speaker materials, provided you know what you are doing.
Hi Paul. You did a great job of explaining resonances adding to the response curve but you didn't look at the other side A speaker driver makes vibrations and the speaker cabinet's job is to send the speakers vibration out into the listening space. Speaker cabinets that vibrate can also cause nulls in the response curve ( not peaks only ) because they are absorbing some of the vibrations that are suppose to be sent out into the listening space. A rigid well designed stiff cabinet allows the driver to transmit sound into the air, rather than being absorbed by the enclosure material. Just a thought to ponder.
Solid cabinets are absolutely important. You do hear the resonance when you crank up the volume on crappy speaker boxes. That really muddy crappy sound you hear is the resonance messing up the music. Many instruments resonate wooden boxes (like guitar and piano), but they were designed and tuned to sound good. A speaker box isn't designed to reproduce the sound of any instruments, so you want a dead box. Wooden floors resonate too, so unless you want to add resonant bass from the worlds muddiest, boomiest, bloated subwoofer, decouple your boxes from the floor system.
😀 i feel the speakers resonance is good it gives that extra depth to the musicality. Of course a speakers in a wooden box sounds much better than a speakers in a conrete box 😀. In olden days they gave so much importance to speaker design particularly for material and thickness. Those speakers sounded so good because of the boxes. Pulp wood boards and not more than 3/4" thickness.
Back in the late 50's there was a Popular Electronics article on "Clean Sound From the Drainpipe Eight" Using a section of sewer pipe as the enclosure. Then there are the Warfedale sand filled wall enclosures
Wholeheartedly agree as my journey in floorstanders through TDL, Kef (Q & XQ ranges) finally to a second-hand set of Wilson Benesch ACT ONEs the precision and musicality of speakers increased as the cabinets got sturdier and heavier. Wilson Benesch as a company are really interesting as they use the same drivers in all of their speakers it's the cabinet technology, design and construction that is their usp.
A prime example of cabinet improvement is the difference between the Elac Debut 2.0 vs the Debut Reference. The 2.0 had quite a bit of resonance but the Reference added improved bracing and it’s a huge difference with practically the same driver.
Absolutely true. Speaker cabinet resonances do exist and are detrimental to the sound of a speaker. It will cause peaks and valleys in the frequency response of a loudspeaker. The goal is to minimize these resonances so they do not add colorations to the sound.
This is hugely important. Paul makes that clear well. It's one thing you can easily measure btw. A waterfall measurement, where you also measure the decay, can reveal this behavior. A speaker with a perfect frequency response might not have a perfect waterfall graph. Great speakers stop "speaking" quickly when the intended sound wave stops. Before listening to a new speaker I always knock on the cabinet first. TVs are notoriously bad on this issue and if you knock on the back cover you might realize one major reason why your TV sounds so bad and why you need to connect it to a proper system.
Fat Rat Yes, but cabinet resonances are a great concern for any respectable speaker maker. The CX-100s I just put in the garage are made of thick aluminum and are as quiet as anything can be. Some live music really can do well in that garage. But music not intended to sound live is bad in that setup. Where can I read about what Harbeth is doing special?
Absolutely. Cabinet resonances are spurious noise sources and need to be minimized to make a good loudspeaker. There are quite a few ways to skin the cat 🐈 but a designer that can do it at a reasonable cost is a great designer.
@Fat Rat Here's a funny anecdote. An Alan Shaw used to work for me as a electronic technician back in the early 1980s. At the time I was managing the Test Department for a Audio/Video manufacturer named Thomson CSF Broadcast, a company that was sold by CBS to Thomson a French electronics conglomerate. This turned out to be the springboard for me to get into the CBS Technology Center and work with some well known names and inventors in the science of audio and video. Anyway, a different guy of course but a funny coincidence.
This is completely true. I made my own speakers using 18mm Birch ply....I then lined the inside of the cabinet with 10mm dense rubber, and the speaker just sounded quieter, with less interaction from the cabinet. Paul, check our Acoustic Energy reference series speaker construction. They sandwich a plastic / rubber layer between two thin, 5mm ish sheets of mdf for all the external walls, with lots of bracing internally. Its very effective. The BBC research papers that Harbeth speakers refer to, say they found thinner materials sounding better than thicker sheets. Probably because its storing less energy. Using a hybrid technique, like Acoustic Energy seems like a good solution.
If you listen to a pair of box type speakers at high or normal volume levels, the speakers radiate the same sound pressure level you are experiencing right back into the same small box, wich resonates and mixes into your soundstage.. Another resonance source wich ruin sound is HF/MF driver outside corner/box reflexes, wich can easily destroy sound quality. This was demonstrated many moons ago , A magazine tested several HF drivers mounted on either a normal box, or a box with a heavily damped baffle with 25mm rockwool, and cutouts, and the difference in measured and percieved accuracy shocked them, so resonance is a problem imo :)
Passive radiators resonate more than anything. High fidelity excludes resonances. Fidelity referring to the output matching the input. If you want high fidelity speakers you can't have ports or passive radiators as these do not accurately reproduce the signal. Think I'm wrong, ha. Go ahead and play some music through a speaker with a port and record the output. Play that recording through the speaker and repeat that path three to five times. The slow, late, ringing bass will get exaggerated so you know what to listen for. The initial transient bass response only includes the woofer output. So it may only extend down to 50 Hz. Several cycles of bass later the resonators (ports or radiators) start to ring and produce output late and continue to ring after the signal is gone. Look at the wave form of a plucked bass or bass drum. The short peak with exponential decay is the waveform. That peak gets compressed because the port doesn't produce it. Ported speakers are driven by the old school separate component crowd that doesn't want to add any bass equalization. Replace that port with a second woofer and then apply a Linkwitz transform to get deep accurate bass. Sell those ported speakers to a "friend" while you can. Sealed high fidelity speakers for me thanks.
I don't know if it's worth putting padding or polyfil or fiberglass into a speaker... I want to know, for general quality of sound or even just peace of mind, if it is worth putting stuff inside of a speaker box, and how does the physics of that even work? Is it to deaden the vibration of the cabinet material? I'm in a rough spot where I can't find any definite answers, should it really matter? Why do people make such a big deal about it if it's just a sales pitch?
My friend Janos from Real World Audio builds speakers with live cabinets. Definitely different strokes for different folks and both designs can sound great.
I was just building a 2x12 speaker cab. While sanding the edges with an electric sander the cabinet would start to sing at 212 hertz, much like running your finger along the brim of a glass. I measured it with a guitar tuner.
Yeah, eliminating cabinet resonance is about as far from a gimmick as anything in speaker design and building can get. It is measurable, and pretty easy to hear. I spent years building high end speakers with a friend, who is now an engineer at high end speaker company in Southern California, and we would always use a simple MDF enclosure to get the design in the ballpark of testing and sounding in the ballpark of where we wanted it. But when it came time for final changes, and getting the design to be dialed in, we would always build an enclosure with constrained layer damping, extensive bracing, extra thick baffles, etc. And the better the drivers and crossover components were, the more important getting the cabinet out of the way became.
Solution; remove the cabinet from the equation. 1.) Open Baffle for the win! 2.) Infinite Baffle for the win! I designed and constructed an attic mounted IB serving our primary media room. There's nothing like the way an IB makes bass! As far as Open Baffle speakers, I've built and experimented with DIY'ing a pair but settled on other approaches. Looking forward to further exploration...
Many years ago one of my neighbours had some really nice floorstanding speakers they sounded fantastic he then told me they where actually made from concrete he also said if I could pick one up I could have them needles to say I couldn’t pick it up, way to heavy. He has since past away I often wander what became of them, I hope they still exist
A closed non-resonant cabinet design for a passive 3-way is a waste of effort without the careful consideration of implementation and cost for completely isolating the midrange driver, as you typically see with tweeters in 2-way designs. Tweeters are typically closed on their own, which facilitates mitigating cost.
When i was younger, i was a Technics fan boy. I had very unusual Technics monitors, probably from the 80's. They were 3-way, working as closed box or bass reflex - you choose by the flip of an plate, 4 or 8 Ohms - switchable, all drivers - metal honeycomb, quite big x-over, and the cabinet was aluminium. Very small, bass driver had only 11cm afair, but very heavy. I hope they are still somewhere in my Parents home, i never sell my audio. They were looking like stuff form XXII century, and the quality of build was really very high, but sound was not the greatest. In fact they sounded much worse than my DIY speakers on a set of old Japanese full-range + tweeter drivers. Excuse my English.
I agree with most of your opinions here (and every video) yet I think energy is an important factor in why you should prevent most cabinet resonances. The energy used to move the cabinets walls is wasted energy from the drivers, which go into the listening room instead with less resonance. A totally 'dead' cabinet sounds awful though, I like some 'life' from the cabinets
I would say that even if you consider yourself a budget audiophile or don’t want to spend lots of money, you still owe it to yourself to try our speakers with a good inert cabinet(kef ls50 on sale 8-900??). Getting moderately priced speakers with a good cabinet still falls well working the laws of diminishing returns. I’m actually selling some well regarded towers because I can hear the cabinet. I think it makes a huge difference.
Interesting. While I don't disagree, there's a lot of manufacturers who don't subscribe to that philosophy, rather tuning a more lively/lossy cabinets instead, saying that it needs to work with the drivers, and tuning the resonances lower so they're out of the midrange where they'd be more objectionable. Harbeth, Totem, Audio Note, Devore Fidelity, Snell, are a few that come to mind. I also doubt that concrete sounds very good as a cabinet material.
Acora speakers use granite in the cabinet = no resonance. On the opposite end Harbeth uses the cabinet wood to enhance the sound apparently for mostly the midrange. Different approaches to design with excellent results. Then look at a very unusual design by BAYZ-audio speakers from Hungary I saw at Axpona in 2019 with excellent sound. PS Audio has a lot of tough competition ---------- I wish them well.
It IS a Gimmick! USE Your boxes AS passive radiators. They ALL make Resonance anyway. I'd rather have Good Resonance in MY boxes than even a little Bad Resonance coming off of them. Maybe i'm just Old school? LET'M BREATH & Bellar!
I'm looking for a diy design to mount a 10 inch Tannoy dual concentric at the top of a concrete or clay pipe, firing upwards against the tip of a marble or resin cone for even dispersal.
On a more interesting note, I have read about speaker designers who tune their cabinet resonance to make it resonate at frequencies that are less annoying. This should be more practical than trying to deaden them all together. I am not sure if this is true (as practice) and if it is a viable practice but it does intrigue me.
Loudspeaker cabinet resonances can never be used to an advantage. They are just random spurious resonances that add noise and distortion to the speaker output. Harbeth can change the resonant frequencies and amplitudes by variations in cabinet construction to spread out the resonant frequencies and lower their amplitudes but using the cabinet resonances to any advantage is not possible. All respective speaker manufacturers do this or should do this anyway.
May I ask a dumb question? If resonance is a big part of a speaker sounding good, why don't high end manufacturers line the interior with dynamat or a roll-on sound deadener? I cant seem to find anything regarding this, not even on DIY speaker videos. If you want to kill resonance, coat the interior in a material that kills vibration. I know this liquid, spreadable material exists... I've used it. Just not for this application. What gives?
Unlike distortion, cabinet resonance is a linear response, so its contribution to the overall sound (measured as a percentage) does not decrease at lower volumes. That is, there isn't a certain sound level you have to hit before it becomes a problem; it is a common misconception that it only matters at high sound levels. Just like frequency response and driver resonance, it has the same effect across a wide dynamic range. That is not to say that cabinets (and objects in the room) cannot have sounds that they only produce at high levels, due to defects like loose parts or screws, cracked joints, etc., but basic cabinet resonance won't disappear as you turn the volume down.
@Fat Rat Marrianne is absolutely right. Also you may have heard this before but here we go again : Loudspeaker cabinet resonances can never be used to an advantage. They are just random spurious resonances that add noise and distortion to the speaker output. Harbeth can change the resonant frequencies and amplitudes by variations in cabinet construction to spread out the resonant frequencies and lower their amplitudes but using the cabinet resonances to any advantage is not possible. All respective speaker manufacturers do this or should do this anyway.
@Fat Rat Enginear - I like that. Very appropriate title, but I'm waiting to hear back from him regarding whether or not he can hear the distortion in the "Out of Thin Air" track 1, before awarding him the title. I sent him a de-clipped version that he can do A-B comparisons with.
@Fat Rat What's noteworthy, is that all of the peaks on track 1 hit precisely -3dB and that is when distortion is audible. Other tracks exceed -3dB without distortion. My best guess so far, is that someone didn't notice a limiter switch was set to ON when they recorded that track.
No mather what you do , its impossible to elliminate the cabinet resonating. Even if it was concrete. Thatone is indeed true. But there are ways to reduce , and disperse over a wider band. A lot better Than having a box resonating at a single freqvency or over a narrow range and with high amplitude. So its bettet to first start with a proper design that aims to spread the resonance over a wide range and then , only then proceed to how to dampen those.
But sometimes we overlook the obvious: That the drivers on the front panel should not move. Think of it as camera blur in reverse. The whole front panel is facing you, in the sum of its total output, the panel is undisguisable from the drivers. This is where I concentrate my best effort in designing speakers. I want that focus above anything else.
Speaker housings made from cast concrete, yes? Would not have occurred to me, but why not, easy enough to do, with the right inner and outer moulds from plywood or MDF. Did that when I was in my 20ies, cheap steel tube plus glass Hifi-racks, just plugged the plastic caps on to of the tubes off, fitted them with long M8 bolts, lots of nuts and big steel washers along the length, , filled the tubes with concrete, hammered in the plastic tops plus bolts and everything top and bottom, and that were my super heavy Hi-Fi-stands. Any ideas, anyone, what might happen if I were to exactly replicate the inner dimensions of my aged Mission 775 floor standers with some wood, holes for the drivers and wiring and all, outer case a thickness around that by dint, to then "remake" them from concrete, outer coating then not so much to the point? Inner lining, bitumen or sth. recommended?
why can't we have speakers without cabinets. they should be able to levitate in mid air, and have the levitation circuit effectively isolated from the speaker wires so there's no interference. in fact we could have wireless speakers (which everybody knows BT audio provides the cleanest audio listening experience) and then... three levitating speakers that rotate, just like Jimi H. idk why this isn't a thing, i don't see any reason why it shouldn't be.
BBC thought otherwise, their thoughts was to control the resonance as their thinking was that you can not escape it, I have a pair of Graham Audio LS5/9, violins, piano, all acoustic instruments sound just sublime, they lack deep bass, but I like a sub for that anyway. Having heard many speakers with so-called dead cabinets, must say owning the 5/9 I for one prefer the BBC design way of thinking 🙂
That's a easy one ;-) Turn up the volume, and then put your hands on the speaker cabinet. If it's shaken and you feel vibrations, then you need some good isolation, and that's it! Cheers from Denmark (btw Paul....did you loose weight over the summer?) You look healthy and more slim ;-)
I used to own a pair of passive radiator Avance's that had a concrete/woodchip construction. Curved sides, bumpy surface, fast bass, vifa drivers, and not too bad 'waffed' against a wall. Speaking of which; they were white with two dreadful pinstrips down the black grilles. They were almost waffed out the house, though pulling these pinstripes off was the dramatic improvement that led to permission for their retention. Always a good idea then add some tasteless flourish to new gear, so you can 'compromise' by taking it off again! (shhh - I won't tell anyone) N.B. my new word 'waffed' = subjected to an action due to a poor 'wife' acceptance factor - to be PC; note hyphens - 'wife' can be applied to either(any) sex.
My best subwoofer was 3 concrete stormwater drain tubes stacked vertically with a 15" woofer at the top on a solid wood baffle. It stood 5 feet high. Did it resonate? Not a chance. Did it look ugly? Oh yes.
I was asking myself this question. I want to do a carbon fiber cabinets, and was thinking about non-traditional shapes that might be functional for minimizing vibration and interesting to look at.
@@Paul58069 Carbon fiber in a thin sheet will vibrate (i.e. carbon fiber instruments), but in a laminate with the right core material, it will be super rigid. and well damped. It is not practical, but should work if I ever get around to it.
@@fredygump5578 Carbon sheets with a different core material inbetween won't do much strenghtwise. Carbon fibre is only strong when it is layered with another sheet of carbon fibre and then cross or diagonal orientation for the weaving. But I appreciate your quest for finding something leftfield that could work.
@@Paul58069 Clearly you do not have ANY knowledge of composites! Laminating over a core material is literally THE WAY to make a strong and light weight panel.
@@fredygump5578 I must take your word for it, I am indeed no expert in this field. I hope it will work out for you. What core material do you have in mind ?
@Fat Rat Using No-Rez inside the cabinets and heavy blankets on the outside of them is even better,. Then using plenty of bracing inside to raise the resonant frequencies to make them easier to damp is still better.
@Fat Rat What they are doing is let them flex at their lowest frequency (because of no bracing) and use lots of damping material and possibly high loss wood as well to damp the resonances. If they used bracing, it would raise the resonant frequencies which would make the damping more effective. They aren't tuning anything. Any resonance is potentially disruptive at any audible frequency.
@Fat Rat I may not be an expert on everything, but I know a thing or two about resonance and damping which I began learning about in 1968 in electronics class. Harbeth has no reason to change because they are very successful in their approach. There are too few companies that go as far with cabinet resonances as they do and I commend them for it.
Back in the 70's and 80's, as I remember it, the danish speaker company Avance had a series called Concrete, as their cabinets where made from a special kind of concrete, as ordinary concrete are ringing at higher frequincies. www.google.com/search?q=Avance+Concrete
I've heard of (but, not heard, just throwing this out for information purposes) a Danish company called JERN Aps that makes small 2-way speakers with cast iron cabinets, claimed to be very non-resonanant. Their merged double spheroid shape (I know, weird, but I can't come up with a better description, except) that kind of reminds me of a Shmoo, a mythical little critter created by cartoonist Al Capp, except without the face and stubby legs and feet. Also there are planar speakers, like Magnepan that have a frame CNC milled from "a quotidian[?] sheet of trusty MDF; dimentionally stable, homogeneous in all three dimensions, and inexpensive."
@Fat Rat Loudspeaker cabinet resonances can never be used to an advantage. They are just random spurious resonances that add noise and distortion to the speaker output. Harbeth can change the resonant frequencies and amplitudes by variations in cabinet construction to spread out the resonant frequencies and lower their amplitudes but using the cabinet resonances to any advantage is not possible. All respective speaker manufacturers do this or should do this anyway. This is starting to get old. 😉
@@StewartMarkley And yet Harbeths and BBC based designs in general still sound so bloody good! Too rich for my modest socio-economic status, but compared to halo products from Wilson, Magico, et al. they are quite reasonably priced. Hey, Mr. Rat. Good comment, not old at all. ;-)
@@stephensmith3111 Agreed. A sign of a superior speaker company in my opinion is making a great sounding design that is affordable at the same time. I am just pointing out that resonances of any nature in a speaker is not advantageous. Ideally all sources of resonances in a loudspeaker should be damped (minimized) as much as possible.
There are two ways of dealing with resonances, everything resonates at some frequency but you can either deal with it by sheer mass and rigidity - think electron microscope sitting on a massive concrete slab 2) ultra light and rigid to reduce the duration of the vibration and shift them up out of the audible range. Magico/Wilson use the first method and Harbeth the second.
@@petersouthernboy6327 really? cuz all the reading ive done suggests that aluminum is great at transmitting vibrations, not damping them, and magnesium (some alloys in particular) are used in aerospace specifically for their high damping factor. genuinely very interested in learning more if you have a source or something that you can share
Crokto - magnesium, lead, and zinc alloys have a slightly better Young’s Modulus than aluminum - but magnesium is much more expensive than aluminum. As a matter of fact, I don’t know where you’d get commercially available preformed structural magnesium materials like angle or sheet or bar - magnesium has to be cast or forged.
@@petersouthernboy6327 i never said it was *cheap*, but if youre gonna charge 6 figures for the speaker its definitely still in the range of affordability. casting is going to be the best method anyways to get the sorts of shapes you want, but you can get sheet or bar stock on alibaba for example. you can totes machine it, it just might explode is all (but there are shops that specialize in this and precautions you can take). young's modulus also isnt the only factor, but also a materials internal damping, a process which converts vibration to heat. from what i understand, many machinist tools are made from cast iron rather than steel because cast iron has better internal damping properties, and magnesium has much better internal damping than most similar metals.
That's why you shouldn't... have a speaker fitted to the front baffle it should be fastened on the magnet on the inside dramatically reduces mechanical resonance, What's happening is it getting back into the vocal coil and smearing the sound and actually cancelling some parts of the frequency I think what Paul is trying to say. There's a few ways to do it but what's wrong with putting the bracing like bamboo 12mm in a diagonal cross member side to side and have it under tension the sidewalls, so it is cupping from the outside 3 mm in at it's narrowest point held in place by the tension of the brace, as I have told you use thin walls is the proper way to go much easier to manipulate and strengthen and has less resonance and is better sounding then thick wall cabinets, as long as there's plenty of bracing like with partitions honeycomb structure so no big area is not braced probably about 2 or 3 inches at the most open area, the bracing goes vertically not across it is incorporated into the side panels same principle as an egg box it is thin but strong and stiff what you can stand on and it will take your weight without eggs of course lol, make your side walls out of honeycomb plywood 3 mm thick by about 12mm in depth strips of Marine beach plywood, the outer wall can be about 6mm thick plywood or hardboard, glued and clamped together into any shape you want. you need to find a good cabinet maker shop use thin epoxy resin when gluing ideally under a vacuum what is easily achieved and cheap not expensive In a mould. This could be achieved with fibreglass in the same principle and would be cheaper the mold would be shaped to Incorporated with the Honeycomb structure in it a thin veneer could be used on the outside of a millimetre thick or any other material for that matter
I sure you are the inspiration for the series "Warehouse 13" and the film "Paul"..... Knew i'd track the truth down on youtube....My question is: What other uses for amplifiers and sonic equiptment have "THEY" got? The aerial shots in your credits allways trigger this thought :)
It's simple ... it's all about the size of the radiating surface. The sheer size and amount of cabinet surface area determines that the slightest panel excitation produces significant amounts of acoustic output.
I have an app on my phone that measures even the tiniest vibrations,placed my phone on one of my speakers and cranked it up. No vibrations at all or very minute during some heavy bass music.
The vibration that goes hundreds of times a second will not show up on your phone unless you glue your phone to the speaker. And it can be the back or side plate that vibrate, not the top plate which usually is small. Smaller surfaces have higher pitched self resonances. If you knock on different parts of your speaker, then you will get an idea what types of resonances your speakers. Every speaker resonnate, but it often is taken better care of in high end models.
@@oysteinsoreide4323 I placed my speakers on its sides and measured also, same response, either no vibration or very minute during heavy bass parts of a song. And the app is very sensitive as it used the phones internal sensors. Just touching the speaker with the tip of my finger while my phone is resting on it shows vibration.
@@dakken74 There is a reason test equipment that measures this stuff is 10K+. Your phone doesn't have calibrated vibration sensors. Why is it that so many think an app on a phone can do everything?
So Paul let me ask you this, how do you explain Andrew Jones turning the Pioneer speakers for $80 that weigh 12 pounds each or his Pioneer Tower or elac budget speakers that are light and don't have a bunch of bracing and they sound fantastic for the money? Ready Set Go!
Loudspeaker cabinet resonances can never be used to an advantage. They are just random spurious resonances that add noise and distortion to the speaker output. Harbeth can change the resonant frequencies and amplitudes by variations in cabinet construction to spread out the resonant frequencies and lower their amplitudes but using the cabinet resonances to any advantage is not possible. All respectible speaker manufacturers do this or should do this anyway.
@Fat Rat Yup, I meant to say respectible, which I consider Harbeth to be because they have managed to make a great sounding speaker that is generally affordable. I haven't heard them but by all accounts they have done a good job with the cost compromises. I stand by my claim that cabinet resonances cannot be used to any advantage. Harbeth hasn't tuned as much as damped the cabinet resonances.
@Fat Rat Tuning refers to altering frequencies, damping is not altering frequencies but damping resonance. Two totally different things. Harbeth has actually done both, by not bracing their cabinet which keeps the resonant frequency as low as it can be for the given size cabinet, and using lots of heavy damping material to damp and also further lower the resonant frequency due to added mass. This lets them keep the resonant frequencies as low as possible which helps keep them out of the critical midrange frequencies but also makes them harder to attenuate. It is by all accounts by successful approach judged by the high praise and acceptance of Harbeth speakers which I commend them for. But I would opt for bracing and raising the frequencies versus lowering them to make the damping more effective. It comes at a higher manufacturing cost though which is obviously important for a speaker manufacturer.
Maybe its not a matter of loudness but of sound coloration due to the integrity of the cabinet. I think you are eliminating variables that can affect the sound and how it is intendet to be reproduced no matter if is at low or high level...
Look it, I’m no expert on speakers but I have, on a number of occasions, listened to a well know British speaker brand that produces very popular speakers that just about jump all over the place with their cabinet resonances. I cannot count the number of reviews of those speakers that tout the cabinet resonances as being part of ‘the sound’. Each to their own I suppose.
Some folks like salt on their fries. And that is fine. It is what makes them happy. But if you want to accurately taste the fries, and know exactly how the fries taste, then salt is a no-no. Speaker designers do all sorts of things to achieve a sound that some segment of the population will like. So that British speaker brand probably sounds very good. But it probably also does not sound realistic, in a purest way. High end speakers tend to aim towards accuracy, their goal being to make every effort to not color the sound; to only project the sound being fed to it. I do not know to which speakers you are referring or anything about the reviews. So this reply is a general statement. By the way, what does "Loki's" mean?
@@clothyardshafts I took a look at Harbeth reviews. One from 10 years ago from Stereophile, and one somewhat recent from The Absolute Sound. One pair was in the $2K price range. The other pair was approximately $15k. Both reviews gave high praise to their respective review models. Naturally the more expensive pair got more praise. The boys at Stereophile and The Absolute Sound do not give praise just to be polite (and is the reason I trust their reviews). So Harbeth seems to be a quality and great sounding speaker line, and has been so for many years.
Yes, within certain design parameters, one style is called 'open baffle' speakers, and yes, they can sound great. But, you still have the same problem, but with a lot less mass and design options for containing/stopping speaker baffle vibration, and a lot of baffle size to control, which is required in order to keep front and back sound emissions from interacting for at least a certain amount of time.
james ross Yes it is possible. Eg planar or panel speakers. I have a pair of full range electrostatic speakers. Flat panels in a frame so they are dipoles and radiate from front and back. No box to resonate and no crossover to cause distortion. Expensive but incredibly fast and low distortion. Once you have heard quality large electrostatics you will never go back to a box speaker.
Absolutely, and I believe I've seen them made of Corian too, and they sounded amazing. So I think it's useful to use something like that. They've made horns from cement all the way back in the 30s.
I think it's glaringly evident that cabinet rigidity plays a MAJOR role in the final product, but the real question is.. WHERE YOU HIDING THE WEEEEEEEEEEEEEEED??
About Cabinet strength properties. Imagine yourself walking in muddy terrain after the rain & your feet being eaten by it. Then imagine yourself riding on a sturdy, dry terrain... That's the difference between an average low grade cabinet & a 300.000$ Wilson Audio Alexx metal reinforced cabinet structure. Need a try ? ----> czcams.com/video/BfzK7XYd0LE/video.html
Jeff Paynter Other planar types and OBs with moving coil drivers have similar theoretical advantages, but then true dipole or bipoles are not absent their own issues with room interactions. There is no universally perfect audio component, and the integration of full bandwidth loudspeakers and “average” domestic venue will always remain an exercise in balancing of compromises. As to the question of ideal method of mitigating or eliminating measurable & audible artifacts of speaker enclosure resonances, I think that’s an Alice in Wonderland rabbit hole in which one can too easily be entrapped.
I hate to say it but he's right, graphs are shown and discussed in this video by Hexibase "Treating Enclosure Resonances": czcams.com/video/OtvDQY9-63g/video.html It's not immediately clear that these are noticeable, but they're measurable, which is more than can be said about some of these topics.
Decay problems are measurable but rarely do you see such measurements in the specs made public. Lots of audiophiles claiming you can't judge a speaker on measurements are right that you can't judge everything, but you can still judge a lot.
dakken74 Yeah, not exactly the same root cause but sort of the same issue of poor sound decay performance. Poor decay can happen due to several factors. Also your amps damping factor plays a role.
Very simple experiment: take a driver emitting at or above normal speech volume output (75dB and above) and let it play in free air.
Then press the magnet (the heaviest therefore hardest to excite material of the driver) reasonable firmly on a number of surfaces including speaker cabinets, and listen for the difference.
It’s there and it’s huge.
Speaker cabinets are the single most important contributor to the sound signature once you are out of the treble range.
why don't we have cabinet less speakers.
@@simonlinser8286 We do.
1000% agree! You can add simple bracing to cheap speakers and won't believe the difference.
I found the B&W factory tour CZcams fascinating to realize the lengths they go to build a cabinet. The tweeter in a solid aluminum case and then on a rubber dampener to reduce vibration transfer from the midrange. So I then added a silicone dampener between my bass cabinet and the mid. Wow. Immediate impact to an already good sound. Clearer, less muddy. That is with cabinets made of 1.5" solid walnut.
Some speaker manufacturers make full range speakers that will reproduce 20 Hz accurately and with ease (if the amp is up to the job).
And some of these manufacturers also make subs that are designed to work with their full range speakers.
So why would a speaker, that can easily reproduce every frequency, benefit from a sub? (keeping in mind the goal is for accuracy -- not bloated double bass).
The answer is to minimize the vibration in the main speakers.
When you record video with your camera, you want the camera to remain perfectly still.
When your speaker's drivers produce sound, you want them to remain perfectly still (and, yes, they move in order to produce sound -- I am talking about not moving from external forces).
So by using a high-pass filter for the main speakers, and having the subs, in their own stand-alone cabinets, produce the most violent frequencies, then the main speaker cabinets will vibrate less, resulting in a better focused soundstage with better imaging, etc.
Cheers!
Heard of OIS? Everything moves and it makes the video even better.
In your example, there is more involved than just the cabinets. Since the woofers in full-range speakers usually work into the lower midrange, making them reproduce high-excursion low bass at the same time causes IM distortion of the midrange frequencies. This gets worse as sound level goes up. Offloading high-power low bass to a sub often yields audible improvement in midrange clarity.
Then the only issue we have to contend with, is the same kind of IM distortion in our hearing. As far as I know, no one has been born with subears for those low frequencies.
Also, acoustic interaction in the room. Subs and speakers have different placement requirements.
Oftentimes the ideal position for the Left or Right speaker isn't ideal for the subwoofer. Speakers are to be placed symmetrically, and subs placed according to minimize excitation of resonances. Rarely are those the same place.
Love the stone work in your garden Paul, it looks like you have a great home. Rock solid and low resonance for sure.
When I build my house, it will be built from the ground up to minimize resonance. Nothing more annoying than the usual ~40hz room resonance...from the walls vibrating!
Great answer Paul. The clue is in the question, that's to say, resonance. All solid structures have a resonant frequency. If you introduce vibration they will vibrate too. However, the amplitude of the vibration will increase dramatically at the resonant frequency of the structure.
It's the reason why bridge engineers have to make sure the resonant frequency of the structure is well away from the frequency of swaying caused by a strong wind, otherwise the bridge will tear itself to pieces. There is a famous video of just this effect.
You can damp resonance by using a second material of a different size or density in close proximity to the the primary structure or you can go the stick on suppressor route. An example of the former is the platter on the Linn Sondek LP12. It has an inner platter and separate outer. The two parts have different resonant frequencies and one effectively damps the other. You only need a thin felt mat to support the record.
Yes, as a person who made many speakers, yes it makes a difference.
As an easy DIY could you dynomat the inside of a cabinet for some deadening? Or is there a better easy DIY method?
@@thekittencult I overcloaked mine with floor carpet tiles cut to size and glued to webbing. Very pleased with the result, now I can really hear the speakers clear and sharp !
@@jacksyful Sounds great !
@@vivianvaldi7871 You do realize there's no space between an exclamation point and the last letter of the word at the end of the sentence, right?
@@FeeLtheHertZ l only apply French regulations, sorry for that.
This is Brian again. Paul, you nailed it. The cabinet resonance will definitely reverberate back into the output of the driver. Especially at high volumes. I believe speaker cabinet makers build their units to work at certain peak volume levels and extreme high volumes aren't a big consideration.
Many speaker designs have damping materials inside the cabinet, go figure😉 🤣🤣
It's also significant that cabinet resonance follow driver motion in time and can extend for some considerable period of time after being excited. Additionally, the generally large surface area of a cabinet panel needs only to move a little bit to produce significant output. Thanks for a fine presentation, Paul!
That’s why it’s important to have a good ratio of weight to absolute stiffness.
It’s not good to have something reasonably stiff but with a lot of mass. It will just blubber along anyway in the lower frequencies.
Concrete can sing because it is actually not that stiff, but brittle and hard.
Foam and foamboard are on the other hand not totally crazy speaker materials, provided you know what you are doing.
Hi Paul. You did a great job of explaining resonances adding to the response curve but you didn't look at the other side A speaker driver makes vibrations and the speaker cabinet's job is to send the speakers vibration out into the listening space.
Speaker cabinets that vibrate can also cause nulls in the response curve ( not peaks only ) because they are absorbing some of the vibrations that are suppose to be sent out into the listening space.
A rigid well designed stiff cabinet allows the driver to transmit sound into the air, rather than being absorbed by the enclosure material. Just a thought to ponder.
That's a nice clear thought. It's hard to say what's intended, but it might be a matter of a preference, since it changes the sound.
Solid cabinets are absolutely important. You do hear the resonance when you crank up the volume on crappy speaker boxes. That really muddy crappy sound you hear is the resonance messing up the music. Many instruments resonate wooden boxes (like guitar and piano), but they were designed and tuned to sound good. A speaker box isn't designed to reproduce the sound of any instruments, so you want a dead box. Wooden floors resonate too, so unless you want to add resonant bass from the worlds muddiest, boomiest, bloated subwoofer, decouple your boxes from the floor system.
😀 i feel the speakers resonance is good it gives that extra depth to the musicality. Of course a speakers in a wooden box sounds much better than a speakers in a conrete box 😀. In olden days they gave so much importance to speaker design particularly for material and thickness. Those speakers sounded so good because of the boxes. Pulp wood boards and not more than 3/4" thickness.
100% spot on.
Back in the late 50's there was a Popular Electronics article on "Clean Sound From the Drainpipe Eight" Using a section of sewer pipe as the enclosure. Then there are the Warfedale sand filled wall enclosures
Wholeheartedly agree as my journey in floorstanders through TDL, Kef (Q & XQ ranges) finally to a second-hand set of Wilson Benesch ACT ONEs the precision and musicality of speakers increased as the cabinets got sturdier and heavier. Wilson Benesch as a company are really interesting as they use the same drivers in all of their speakers it's the cabinet technology, design and construction that is their usp.
A prime example of cabinet improvement is the difference between the Elac Debut 2.0 vs the Debut Reference. The 2.0 had quite a bit of resonance but the Reference added improved bracing and it’s a huge difference with practically the same driver.
Thanks for the reference to Magico Audio. Those are some seriously nice speakers! Hope your PS Audio speakers are released soon!!
Absolutely true. Speaker cabinet resonances do exist and are detrimental to the sound of a speaker. It will cause peaks and valleys in the frequency response of a loudspeaker. The goal is to minimize these resonances so they do not add colorations to the sound.
This is hugely important. Paul makes that clear well. It's one thing you can easily measure btw. A waterfall measurement, where you also measure the decay, can reveal this behavior. A speaker with a perfect frequency response might not have a perfect waterfall graph. Great speakers stop "speaking" quickly when the intended sound wave stops. Before listening to a new speaker I always knock on the cabinet first. TVs are notoriously bad on this issue and if you knock on the back cover you might realize one major reason why your TV sounds so bad and why you need to connect it to a proper system.
Fat Rat Yes, but cabinet resonances are a great concern for any respectable speaker maker. The CX-100s I just put in the garage are made of thick aluminum and are as quiet as anything can be. Some live music really can do well in that garage. But music not intended to sound live is bad in that setup. Where can I read about what Harbeth is doing special?
Absolutely. Cabinet resonances are spurious noise sources and need to be minimized to make a good loudspeaker. There are quite a few ways to skin the cat 🐈 but a designer that can do it at a reasonable cost is a great designer.
@@StewartMarkley Yes, it's not rocket science.
@Fat Rat Here's a funny anecdote. An Alan Shaw used to work for me as a electronic technician back in the early 1980s. At the time I was managing the Test Department for a Audio/Video manufacturer named Thomson CSF Broadcast, a company that was sold by CBS to Thomson a French electronics conglomerate. This turned out to be the springboard for me to get into the CBS Technology Center and work with some well known names and inventors in the science of audio and video. Anyway, a different guy of course but a funny coincidence.
that wall paul's sitting on would make a lovely miniature pond !! :)
This is American construction. It would have to be very shallow to hold the pressure. Nearly everything built here is a facade.
This is completely true. I made my own speakers using 18mm Birch ply....I then lined the inside of the cabinet with 10mm dense rubber, and the speaker just sounded quieter, with less interaction from the cabinet.
Paul, check our Acoustic Energy reference series speaker construction. They sandwich a plastic / rubber layer between two thin, 5mm ish sheets of mdf for all the external walls, with lots of bracing internally. Its very effective.
The BBC research papers that Harbeth speakers refer to, say they found thinner materials sounding better than thicker sheets. Probably because its storing less energy. Using a hybrid technique, like Acoustic Energy seems like a good solution.
Thin cabinet wall might give more bass.
But the quality of it might be disputable.
If you listen to a pair of box type speakers at high or normal volume levels, the speakers radiate the same sound pressure level you are experiencing
right back into the same small box, wich resonates and mixes into your soundstage..
Another resonance source wich ruin sound is HF/MF driver outside corner/box reflexes, wich can easily destroy sound quality.
This was demonstrated many moons ago , A magazine tested several HF drivers mounted on either a normal box, or a box with a heavily damped
baffle with 25mm rockwool, and cutouts, and the difference in measured and percieved accuracy shocked them, so resonance is a problem imo :)
I would love to know the name of the guy selling cement speakers for cheap!.
Shipping costs?
Bear in mind, that is cheap using Paul's definition of it as reference.
I'll sell you a cheap cement speaker.
concrete-audio.com. Made in Germany, worldwide shipping.
Homer Bach-Hertz
That's why i build my subs out of 20ml.marble, one drow back though is the weight. Apart from that they look and sound amazing
Passive radiators resonate more than anything. High fidelity excludes resonances. Fidelity referring to the output matching the input. If you want high fidelity speakers you can't have ports or passive radiators as these do not accurately reproduce the signal. Think I'm wrong, ha. Go ahead and play some music through a speaker with a port and record the output. Play that recording through the speaker and repeat that path three to five times. The slow, late, ringing bass will get exaggerated so you know what to listen for. The initial transient bass response only includes the woofer output. So it may only extend down to 50 Hz. Several cycles of bass later the resonators (ports or radiators) start to ring and produce output late and continue to ring after the signal is gone. Look at the wave form of a plucked bass or bass drum. The short peak with exponential decay is the waveform. That peak gets compressed because the port doesn't produce it. Ported speakers are driven by the old school separate component crowd that doesn't want to add any bass equalization. Replace that port with a second woofer and then apply a Linkwitz transform to get deep accurate bass. Sell those ported speakers to a "friend" while you can. Sealed high fidelity speakers for me thanks.
I don't know if it's worth putting padding or polyfil or fiberglass into a speaker... I want to know, for general quality of sound or even just peace of mind, if it is worth putting stuff inside of a speaker box, and how does the physics of that even work? Is it to deaden the vibration of the cabinet material? I'm in a rough spot where I can't find any definite answers, should it really matter? Why do people make such a big deal about it if it's just a sales pitch?
My friend Janos from Real World Audio builds speakers with live cabinets. Definitely different strokes for different folks and both designs can sound great.
I was just building a 2x12 speaker cab. While sanding the edges with an electric sander the cabinet would start to sing at 212 hertz, much like running your finger along the brim of a glass. I measured it with a guitar tuner.
Yeah, eliminating cabinet resonance is about as far from a gimmick as anything in speaker design and building can get.
It is measurable, and pretty easy to hear.
I spent years building high end speakers with a friend, who is now an engineer at high end speaker company in Southern California, and we would always use a simple MDF enclosure to get the design in the ballpark of testing and sounding in the ballpark of where we wanted it.
But when it came time for final changes, and getting the design to be dialed in, we would always build an enclosure with constrained layer damping, extensive bracing, extra thick baffles, etc.
And the better the drivers and crossover components were, the more important getting the cabinet out of the way became.
Solution; remove the cabinet from the equation.
1.) Open Baffle for the win!
2.) Infinite Baffle for the win!
I designed and constructed an attic mounted IB serving our primary media room. There's nothing like the way an IB makes bass!
As far as Open Baffle speakers, I've built and experimented with DIY'ing a pair but settled on other approaches. Looking forward to further exploration...
Many years ago one of my neighbours had some really nice floorstanding speakers they sounded fantastic he then told me they where actually made from concrete he also said if I could pick one up I could have them needles to say I couldn’t pick it up, way to heavy. He has since past away I often wander what became of them, I hope they still exist
A closed non-resonant cabinet design for a passive 3-way is a waste of effort without the careful consideration of implementation and cost for completely isolating the midrange driver, as you typically see with tweeters in 2-way designs. Tweeters are typically closed on their own, which facilitates mitigating cost.
Nomex will do the trick. I'd be more concerned with the reflection on the inside of the cabinet hitting the back of the driver.
When i was younger, i was a Technics fan boy.
I had very unusual Technics monitors, probably from the 80's.
They were 3-way, working as closed box or bass reflex - you choose by the flip of an plate, 4 or 8 Ohms - switchable, all drivers - metal honeycomb, quite big x-over, and the cabinet was aluminium.
Very small, bass driver had only 11cm afair, but very heavy.
I hope they are still somewhere in my Parents home, i never sell my audio.
They were looking like stuff form XXII century, and the quality of build was really very high, but sound was not the greatest.
In fact they sounded much worse than my DIY speakers on a set of old Japanese full-range + tweeter drivers.
Excuse my English.
How about lining the insides of the wooden cabinets with cement for reinforcement...solid on the inside...beauty on the outside...
Dear Paul , good luck matching your future speakers with KEF's .
I agree with most of your opinions here (and every video) yet I think energy is an important factor in why you should prevent most cabinet resonances. The energy used to move the cabinets walls is wasted energy from the drivers, which go into the listening room instead with less resonance. A totally 'dead' cabinet sounds awful though, I like some 'life' from the cabinets
I had no clue PS Audio was based in CO. Small world, howdy neighbor.
I would say that even if you consider yourself a budget audiophile or don’t want to spend lots of money, you still owe it to yourself to try our speakers with a good inert cabinet(kef ls50 on sale 8-900??). Getting moderately priced speakers with a good cabinet still falls well working the laws of diminishing returns. I’m actually selling some well regarded towers because I can hear the cabinet. I think it makes a huge difference.
Interesting. While I don't disagree, there's a lot of manufacturers who don't subscribe to that philosophy, rather tuning a more lively/lossy cabinets instead, saying that it needs to work with the drivers, and tuning the resonances lower so they're out of the midrange where they'd be more objectionable. Harbeth, Totem, Audio Note, Devore Fidelity, Snell, are a few that come to mind. I also doubt that concrete sounds very good as a cabinet material.
Nice crib Mr Paul.
currently adding dynamat sheets to the inside of some cabinets.. man.. what a difference..
Acora speakers use granite in the cabinet = no resonance. On the opposite end Harbeth uses the cabinet wood to enhance the sound apparently for mostly the midrange. Different approaches to design with excellent results. Then look at a very unusual design by BAYZ-audio speakers from Hungary I saw at Axpona in 2019 with excellent sound. PS Audio has a lot of tough competition ---------- I wish them well.
It IS a Gimmick! USE Your boxes AS passive radiators. They ALL make Resonance anyway. I'd rather have Good Resonance in MY boxes than even a little Bad Resonance coming off of them. Maybe i'm just Old school? LET'M BREATH & Bellar!
I'm looking for a diy design to mount a 10 inch Tannoy dual concentric at the top of a concrete or clay pipe, firing upwards against the tip of a marble or resin cone for even dispersal.
On a more interesting note, I have read about speaker designers who tune their cabinet resonance to make it resonate at frequencies that are less annoying. This should be more practical than trying to deaden them all together. I am not sure if this is true (as practice) and if it is a viable practice but it does intrigue me.
Loudspeaker cabinet resonances can never be used to an advantage. They are just random spurious resonances that add noise and distortion to the speaker output. Harbeth can change the resonant frequencies and amplitudes by variations in cabinet construction to spread out the resonant frequencies and lower their amplitudes but using the cabinet resonances to any advantage is not possible. All respective speaker manufacturers do this or should do this anyway.
YG speakers are the best I ever heard.
May I ask a dumb question? If resonance is a big part of a speaker sounding good, why don't high end manufacturers line the interior with dynamat or a roll-on sound deadener? I cant seem to find anything regarding this, not even on DIY speaker videos. If you want to kill resonance, coat the interior in a material that kills vibration. I know this liquid, spreadable material exists... I've used it. Just not for this application. What gives?
And Alan Shaw fans love the resonance
Unlike distortion, cabinet resonance is a linear response, so its contribution to the overall sound (measured as a percentage) does not decrease at lower volumes. That is, there isn't a certain sound level you have to hit before it becomes a problem; it is a common misconception that it only matters at high sound levels.
Just like frequency response and driver resonance, it has the same effect across a wide dynamic range.
That is not to say that cabinets (and objects in the room) cannot have sounds that they only produce at high levels, due to defects like loose parts or screws, cracked joints, etc., but basic cabinet resonance won't disappear as you turn the volume down.
@Fat Rat Marrianne is absolutely right.
Also you may have heard this before but here we go again :
Loudspeaker cabinet resonances can never be used to an advantage. They are just random spurious resonances that add noise and distortion to the speaker output. Harbeth can change the resonant frequencies and amplitudes by variations in cabinet construction to spread out the resonant frequencies and lower their amplitudes but using the cabinet resonances to any advantage is not possible. All respective speaker manufacturers do this or should do this anyway.
@Fat Rat
Enginear - I like that. Very appropriate title, but I'm waiting to hear back from him regarding whether or not he can hear the distortion in the "Out of Thin Air" track 1, before awarding him the title. I sent him a de-clipped version that he can do A-B comparisons with.
@Fat Rat
You haven't seen our email chain.
@Fat Rat
It's running around 35-40%. But I think I could increase that ratio by providing an A-B comparison track.
@Fat Rat
What's noteworthy, is that all of the peaks on track 1 hit precisely -3dB and that is when distortion is audible. Other tracks exceed -3dB without distortion.
My best guess so far, is that someone didn't notice a limiter switch was set to ON when they recorded that track.
No mather what you do , its impossible to elliminate the cabinet resonating. Even if it was concrete. Thatone is indeed true.
But there are ways to reduce , and disperse over a wider band. A lot better Than having a box resonating at a single freqvency or over a narrow range and with high amplitude.
So its bettet to first start with a proper design that aims to spread the resonance over a wide range and then , only then proceed to how to dampen those.
Interesting.
But sometimes we overlook the obvious: That the drivers on the front panel should not move. Think of it as camera blur in reverse. The whole front panel is facing you, in the sum of its total output, the panel is undisguisable from the drivers. This is where I concentrate my best effort in designing speakers. I want that focus above anything else.
I would love to see Your cabinets.
Speaker housings made from cast concrete, yes? Would not have occurred to me, but why not, easy enough to do, with the right inner and outer moulds from plywood or MDF.
Did that when I was in my 20ies, cheap steel tube plus glass Hifi-racks, just plugged the plastic caps on to of the tubes off, fitted them with long M8 bolts, lots of nuts and big steel washers along the length, , filled the tubes with concrete, hammered in the plastic tops plus bolts and everything top and bottom, and that were my super heavy Hi-Fi-stands.
Any ideas, anyone, what might happen if I were to exactly replicate the inner dimensions of my aged Mission 775 floor standers with some wood, holes for the drivers and wiring and all, outer case a thickness around that by dint, to then "remake" them from concrete, outer coating then not so much to the point? Inner lining, bitumen or sth. recommended?
why can't we have speakers without cabinets. they should be able to levitate in mid air, and have the levitation circuit effectively isolated from the speaker wires so there's no interference. in fact we could have wireless speakers (which everybody knows BT audio provides the cleanest audio listening experience) and then... three levitating speakers that rotate, just like Jimi H. idk why this isn't a thing, i don't see any reason why it shouldn't be.
springs put in box on wall.......then second wall......a?
BBC thought otherwise, their thoughts was to control the resonance as their thinking was that you can not escape it, I have a pair of Graham Audio LS5/9, violins, piano, all acoustic instruments sound just sublime, they lack deep bass, but I like a sub for that anyway. Having heard many speakers with so-called dead cabinets, must say owning the 5/9 I for one prefer the BBC design way of thinking 🙂
The LS5 is such a small speaker cabinet that the walls are very stiff by default
That's a easy one ;-) Turn up the volume, and then put your hands on the speaker cabinet. If it's shaken and you feel vibrations, then you need some good isolation, and that's it! Cheers from Denmark (btw Paul....did you loose weight over the summer?) You look healthy and more slim ;-)
I used to own a pair of passive radiator Avance's that had a concrete/woodchip construction. Curved sides, bumpy surface, fast bass, vifa drivers, and not too bad 'waffed' against a wall. Speaking of which; they were white with two dreadful pinstrips down the black grilles. They were almost waffed out the house, though pulling these pinstripes off was the dramatic improvement that led to permission for their retention. Always a good idea then add some tasteless flourish to new gear, so you can 'compromise' by taking it off again! (shhh - I won't tell anyone)
N.B. my new word 'waffed' = subjected to an action due to a poor 'wife' acceptance factor - to be PC; note hyphens - 'wife' can be applied to either(any) sex.
*Vifa drivers.
@@jareknowak8712 Typo! viva la vifa
I read a long time ago that the best material for enclosures is concrete.
My best subwoofer was 3 concrete stormwater drain tubes stacked vertically with a 15" woofer at the top on a solid wood baffle. It stood 5 feet high. Did it resonate? Not a chance. Did it look ugly? Oh yes.
Remeber the guys ,who used poured concrete for a cabinet? Doc BC
I was asking myself this question. I want to do a carbon fiber cabinets, and was thinking about non-traditional shapes that might be functional for minimizing vibration and interesting to look at.
don do it. Carbon vibrates like hell.
@@Paul58069 Carbon fiber in a thin sheet will vibrate (i.e. carbon fiber instruments), but in a laminate with the right core material, it will be super rigid. and well damped. It is not practical, but should work if I ever get around to it.
@@fredygump5578 Carbon sheets with a different core material inbetween won't do much strenghtwise. Carbon fibre is only strong when it is layered with another sheet of carbon fibre and then cross or diagonal orientation for the weaving. But I appreciate your quest for finding something leftfield that could work.
@@Paul58069 Clearly you do not have ANY knowledge of composites! Laminating over a core material is literally THE WAY to make a strong and light weight panel.
@@fredygump5578 I must take your word for it, I am indeed no expert in this field. I hope it will work out for you. What core material do you have in mind ?
I once lined some speakers with carpet and they sounded much better.
@Fat Rat Using No-Rez inside the cabinets and heavy blankets on the outside of them is even better,. Then using plenty of bracing inside to raise the resonant frequencies to make them easier to damp is still better.
@Fat Rat What they are doing is let them flex at their lowest frequency (because of no bracing) and use lots of damping material and possibly high loss wood as well to damp the resonances. If they used bracing, it would raise the resonant frequencies which would make the damping more effective. They aren't tuning anything. Any resonance is potentially disruptive at any audible frequency.
@@StewartMarkley bracing and inside damping will change the Thiele-Small parameters.
@Fat Rat I may not be an expert on everything, but I know a thing or two about resonance and damping which I began learning about in 1968 in electronics class.
Harbeth has no reason to change because they are very successful in their approach. There are too few companies that go as far with cabinet resonances as they do and I commend them for it.
Back in the 70's and 80's, as I remember it, the danish speaker company Avance had a series called Concrete, as their cabinets where made from a special kind of concrete, as ordinary concrete are ringing at higher frequincies.
www.google.com/search?q=Avance+Concrete
I've heard of (but, not heard, just throwing this out for information purposes) a Danish company called JERN Aps that makes small 2-way speakers with cast iron cabinets, claimed to be very non-resonanant. Their merged double spheroid shape (I know, weird, but I can't come up with a better description, except) that kind of reminds me of a Shmoo, a mythical little critter created by cartoonist Al Capp, except without the face and stubby legs and feet.
Also there are planar speakers, like Magnepan that have a frame CNC milled from "a quotidian[?] sheet of trusty MDF; dimentionally stable, homogeneous in all three dimensions, and inexpensive."
@Fat Rat Loudspeaker cabinet resonances can never be used to an advantage. They are just random spurious resonances that add noise and distortion to the speaker output. Harbeth can change the resonant frequencies and amplitudes by variations in cabinet construction to spread out the resonant frequencies and lower their amplitudes but using the cabinet resonances to any advantage is not possible. All respective speaker manufacturers do this or should do this anyway.
This is starting to get old. 😉
@@StewartMarkley And yet Harbeths and BBC based designs in general still sound so bloody good! Too rich for my modest socio-economic status, but compared to halo products from Wilson, Magico, et al. they are quite reasonably priced.
Hey, Mr. Rat. Good comment, not old at all. ;-)
@Fat Rat You can't change the laws of physics, but sometimes you can finesse them a little if you're very clever, like Alan Shaw.
@@stephensmith3111 Agreed. A sign of a superior speaker company in my opinion is making a great sounding design that is affordable at the same time. I am just pointing out that resonances of any nature in a speaker is not advantageous. Ideally all sources of resonances in a loudspeaker should be damped (minimized) as much as possible.
Just wondering is anyone here has tried Dynamat on the inside of their speaker walls? It's very effective in car audio in stopping vibrations.
How about Harbeth?
There are two ways of dealing with resonances, everything resonates at some frequency but you can either deal with it by sheer mass and rigidity - think electron microscope sitting on a massive concrete slab 2) ultra light and rigid to reduce the duration of the vibration and shift them up out of the audible range. Magico/Wilson use the first method and Harbeth the second.
Paul, when are you going to show us the Barns and Horse Track?
Solid aluminum? I bet they were the tingiest things on the market.
Oh, quite the opposite. Deader than doornails. Big, thick, heavy. break your knuckles strong.
Aluminum is the “deadest” metal there is. I’ve used it to great effect for speaker cabinet bracing in fact.
this is why i think magnesium is the best material. not too expensive to cast, great internal damping properties, lightweight and super rigid
Aluminum is a “deader” metal than magnesium.
Plus magnesium is very $$$$$$$$$$$$$
@@petersouthernboy6327 really? cuz all the reading ive done suggests that aluminum is great at transmitting vibrations, not damping them, and magnesium (some alloys in particular) are used in aerospace specifically for their high damping factor. genuinely very interested in learning more if you have a source or something that you can share
Crokto - magnesium, lead, and zinc alloys have a slightly better Young’s Modulus than aluminum - but magnesium is much more expensive than aluminum. As a matter of fact, I don’t know where you’d get commercially available preformed structural magnesium materials like angle or sheet or bar - magnesium has to be cast or forged.
@@petersouthernboy6327 i never said it was *cheap*, but if youre gonna charge 6 figures for the speaker its definitely still in the range of affordability. casting is going to be the best method anyways to get the sorts of shapes you want, but you can get sheet or bar stock on alibaba for example. you can totes machine it, it just might explode is all (but there are shops that specialize in this and precautions you can take). young's modulus also isnt the only factor, but also a materials internal damping, a process which converts vibration to heat. from what i understand, many machinist tools are made from cast iron rather than steel because cast iron has better internal damping properties, and magnesium has much better internal damping than most similar metals.
Crokto - it would be much more worthwhile to put that money and effort into the drivers and crossovers.
That's why you shouldn't... have a speaker fitted to the front baffle it should be fastened on the magnet on the inside dramatically reduces mechanical resonance,
What's happening is it getting back into the vocal coil and smearing the sound and actually cancelling some parts of the frequency I think what Paul is trying to say.
There's a few ways to do it but what's wrong with putting the bracing like bamboo 12mm in a diagonal cross member side to side and have it under tension the sidewalls, so it is cupping from the outside 3 mm in at it's narrowest point held in place by the tension of the brace, as I have told you use thin walls is the proper way to go much easier to manipulate and strengthen and has less resonance and is better sounding then thick wall cabinets, as long as there's plenty of bracing like with partitions honeycomb structure so no big area is not braced probably about 2 or 3 inches at the most open area, the bracing goes vertically not across it is incorporated into the side panels same principle as an egg box it is thin but strong and stiff what you can stand on and it will take your weight without eggs of course lol, make your side walls out of honeycomb plywood 3 mm thick by about 12mm in depth strips of Marine beach plywood, the outer wall can be about 6mm thick plywood or hardboard, glued and clamped together into any shape you want. you need to find a good cabinet maker shop use thin epoxy resin when gluing ideally under a vacuum what is easily achieved and cheap not expensive In a mould. This could be achieved with fibreglass in the same principle and would be cheaper the mold would be shaped to Incorporated with the Honeycomb structure in it a thin veneer could be used on the outside of a millimetre thick or any other material for that matter
I sure you are the inspiration for the series "Warehouse 13" and the film "Paul"..... Knew i'd track the truth down on youtube....My question is: What other uses for amplifiers and sonic equiptment have "THEY" got? The aerial shots in your credits allways trigger this thought :)
So no cabinets would make the best speaker? Why not drop the cabinet all togeather?
It's simple ... it's all about the size of the radiating surface.
The sheer size and amount of cabinet surface area determines that the slightest panel excitation produces significant amounts of acoustic output.
I have an app on my phone that measures even the tiniest vibrations,placed my phone on one of my speakers and cranked it up. No vibrations at all or very minute during some heavy bass music.
The vibration that goes hundreds of times a second will not show up on your phone unless you glue your phone to the speaker. And it can be the back or side plate that vibrate, not the top plate which usually is small. Smaller surfaces have higher pitched self resonances. If you knock on different parts of your speaker, then you will get an idea what types of resonances your speakers. Every speaker resonnate, but it often is taken better care of in high end models.
@@oysteinsoreide4323 I placed my speakers on its sides and measured also, same response, either no vibration or very minute during heavy bass parts of a song. And the app is very sensitive as it used the phones internal sensors. Just touching the speaker with the tip of my finger while my phone is resting on it shows vibration.
@@dakken74
What is the model of Your speakers?
It might be corealted with frequency of vibrations, not sensivity.
@@dakken74 There is a reason test equipment that measures this stuff is 10K+. Your phone doesn't have calibrated vibration sensors. Why is it that so many think an app on a phone can do everything?
@@MrCarlsonsLab I know my phone's sensors are limited, bit there also a lot better than people give them credit for.
So Paul let me ask you this, how do you explain Andrew Jones turning the Pioneer speakers for $80 that weigh 12 pounds each or his Pioneer Tower or elac budget speakers that are light and don't have a bunch of bracing and they sound fantastic for the money? Ready Set Go!
Loudspeaker cabinet resonances can never be used to an advantage. They are just random spurious resonances that add noise and distortion to the speaker output. Harbeth can change the resonant frequencies and amplitudes by variations in cabinet construction to spread out the resonant frequencies and lower their amplitudes but using the cabinet resonances to any advantage is not possible. All respectible speaker manufacturers do this or should do this anyway.
@Fat Rat Yup, I meant to say respectible, which I consider Harbeth to be because they have managed to make a great sounding speaker that is generally affordable. I haven't heard them but by all accounts they have done a good job with the cost compromises. I stand by my claim that cabinet resonances cannot be used to any advantage. Harbeth hasn't tuned as much as damped the cabinet resonances.
Small cabinets are used to be more rigid than big speakers.
@Fat Rat Tuning refers to altering frequencies, damping is not altering frequencies but damping resonance. Two totally different things. Harbeth has actually done both, by not bracing their cabinet which keeps the resonant frequency as low as it can be for the given size cabinet, and using lots of heavy damping material to damp and also further lower the resonant frequency due to added mass. This lets them keep the resonant frequencies as low as possible which helps keep them out of the critical midrange frequencies but also makes them harder to attenuate. It is by all accounts by successful approach judged by the high praise and acceptance of Harbeth speakers which I commend them for. But I would opt for bracing and raising the frequencies versus lowering them to make the damping more effective. It comes at a higher manufacturing cost though which is obviously important for a speaker manufacturer.
They’d sound a whole lot better with some bracing and Dynamat
Maybe its not a matter of loudness but of sound coloration due to the integrity of the cabinet. I think you are eliminating variables that can affect the sound and how it is intendet to be reproduced no matter if is at low or high level...
Cement cabinet?? Don't sound very stable. Sure it wasn't concrete?
Look it, I’m no expert on speakers but I have, on a number of occasions, listened to a well know British speaker brand that produces very popular speakers that just about jump all over the place with their cabinet resonances. I cannot count the number of reviews of those speakers that tout the cabinet resonances as being part of ‘the sound’. Each to their own I suppose.
Some folks like salt on their fries. And that is fine. It is what makes them happy.
But if you want to accurately taste the fries, and know exactly how the fries taste, then salt is a no-no.
Speaker designers do all sorts of things to achieve a sound that some segment of the population will like. So that British speaker brand probably sounds very good. But it probably also does not sound realistic, in a purest way.
High end speakers tend to aim towards accuracy, their goal being to make every effort to not color the sound; to only project the sound being fed to it.
I do not know to which speakers you are referring or anything about the reviews. So this reply is a general statement.
By the way, what does "Loki's" mean?
I’ve corrected my typos. I know that I’m probably going to start a war but the brand is Harbeth.
@@clothyardshafts I have heard of them. I am not familiar with them.
Fat Rat. I should probably give them a try in my living room. It’s quite probable that the boominess that I hear is caused by the dealer’s ‘room’.
@@clothyardshafts I took a look at Harbeth reviews. One from 10 years ago from Stereophile, and one somewhat recent from The Absolute Sound.
One pair was in the $2K price range. The other pair was approximately $15k.
Both reviews gave high praise to their respective review models. Naturally the more expensive pair got more praise.
The boys at Stereophile and The Absolute Sound do not give praise just to be polite (and is the reason I trust their reviews).
So Harbeth seems to be a quality and great sounding speaker line, and has been so for many years.
Why do we even need speaker cabinets??? Is it possible to not use them . Would it sound good?
Yes, within certain design parameters, one style is called 'open baffle' speakers, and yes, they can sound great. But, you still have the same problem, but with a lot less mass and design options for containing/stopping speaker baffle vibration, and a lot of baffle size to control, which is required in order to keep front and back sound emissions from interacting for at least a certain amount of time.
james ross Yes it is possible. Eg planar or panel speakers. I have a pair of full range electrostatic speakers. Flat panels in a frame so they are dipoles and radiate from front and back. No box to resonate and no crossover to cause distortion. Expensive but incredibly fast and low distortion. Once you have heard quality large electrostatics you will never go back to a box speaker.
Thanks for the information. I will be putting it to good use.
@@geoff37s38 magnepans are well worth it as well. Quite the Revelation
Open baffle speakers - the whole room plays together with speakers, i mean 3x more than with classic boxes.
Just use 2" depleted uranium plate.
And the BBC decides that they want their cabinet to ring a little ... hmmmmm ... I wonder why they took that path.
i think he's talking 'bout Magico M6
ESLs - no cabinet
Anybody make granite or marble speaker cabinets?
Absolutely, and I believe I've seen them made of Corian too, and they sounded amazing. So I think it's useful to use something like that. They've made horns from cement all the way back in the 30s.
Betonart Audio
Vroemen Audio
Fischer & Fischer
German Highend
Mark Daniel Audio
Common Graig....common....>
I think it's glaringly evident that cabinet rigidity plays a MAJOR role in the final product, but the real question is..
WHERE YOU HIDING THE
WEEEEEEEEEEEEEEED??
When we find the weed...we will be able to figure all this out...and write some great songs to listen to on our great speakers...
I don't believe a completely dead cabinet is to be desired.
The more dead the cabinet the better the sound.
About Cabinet strength properties.
Imagine yourself walking in muddy terrain after the rain & your feet being eaten by it.
Then imagine yourself riding on a sturdy, dry terrain...
That's the difference between an average low grade cabinet & a 300.000$ Wilson Audio Alexx metal reinforced cabinet structure.
Need a try ? ----> czcams.com/video/BfzK7XYd0LE/video.html
Concrete anyone
The best way to get rid of cabinet resonance is not have cabinets. That’s why electrostatics like Quads sound so uncoloured.
Jeff Paynter Other planar types and OBs with moving coil drivers have similar theoretical advantages, but then true dipole or bipoles are not absent their own issues with room interactions. There is no universally perfect audio component, and the integration of full bandwidth loudspeakers and “average” domestic venue will always remain an exercise in balancing of compromises.
As to the question of ideal method of mitigating or eliminating measurable & audible artifacts of speaker enclosure resonances, I think that’s an Alice in Wonderland rabbit hole in which one can too easily be entrapped.
I hate to say it but he's right, graphs are shown and discussed in this video by Hexibase "Treating Enclosure Resonances":
czcams.com/video/OtvDQY9-63g/video.html
It's not immediately clear that these are noticeable, but they're measurable, which is more than can be said about some of these topics.
Decay problems are measurable but rarely do you see such measurements in the specs made public. Lots of audiophiles claiming you can't judge a speaker on measurements are right that you can't judge everything, but you can still judge a lot.
Hexibase was talking about Internal resonance from the sound waves bouncing around and making it back the the woofer.
dakken74 Yeah, not exactly the same root cause but sort of the same issue of poor sound decay performance. Poor decay can happen due to several factors. Also your amps damping factor plays a role.