Danny, I have to say that your knowledge of the intricacies of the audio signal is nothing short of astounding! Thank you for sharing it. As a friend always say:« Your light doesn't dim when you ignite someone else's flame. It just makes the world shine that much brighter...»😉
Thats interesting, so basically you implement the caps in the amp directly after the pre inputs? That sounds even less hard an no need of boxes etc…Its a trade off I understand and if you change speaker you have to adjust but it seems line a good option? Anything I’m missing here?
I was on a mission today to look up what was the best way to do this. For some reason I checked your channel today and there it was. Karma? Maybe, but a big thanks for this vid ! You saved me a bunch of searching and in 15 min you clearly explained it all clearly and concisely. Love your channel ! Hoping to build one of your speaker kits very soon.
I HAVE LEARNED ALOT..and ive discovered something never discussed.. soon ill have enough info so I can give correct presentation.. of my discovery..thanks danny.. you already know what ive learned.
This video is awesome. Especially when you have a subwoofer in your system taking care of the deeper frequencies, you gotta have a high-pass filter for your stereo speakers. It's a bummer that some opinion-maker people in this industry think a subwoofer just need to run in parallel with your small speakers ending up struggling with the lower bass causing a lot of distortion. Especially high-end amplifier companies lack proper solutions for this issue and will often just tell you to connect your subwoofer on the speaker terminals to your stereo speakers completely messing up the lower bass quality, especially at higher volume.
Still savin for the open baffles behind ya! Well the shorter ones. Also learning about even odd order ect ect. BIG thanks for this one, working on sketching out a crossover system, not easy.
Nice and informative video. Those little bookshelfs you've got there must sound really nice with inline filter and a separate subwoofer. I've been following you for a long time and this is the best iteration of those giant killers. It would be nice if you would extend the video and talk about active filters, op amps, pro's and con's (figure it's going to be mostly cons), since you mentioned active circuitry. Cheers, Stefan
Great Video Danny, thanks for sharing your knowledge. I ordered 2 x clarity caps esa 0.047uf crossing at 72hz, took an old decent quality rca cable, cut in half, did the same with a subwoofer cable then drilled 6 holes in a sturdy black VHS tape case. I then threaded the cables through the snuggly fitting holes, stripped the wire then soldered everything together, snapped the case shut and eureka, a fully functioning high pass filter at minimum cost and minimal disruption to the signal path. I hope this helps someone else, shame I can't share the photos
Yep! Rolling off the lowest octave improves every aspect of the mid/woofer's performance. Transient response, vocal clarity, imaging, soundstage, dynamic range...
If you want to work out the value of capacitor for a given input impedance and -3dB point use this equation, C=1/(2πZfc) Where C is the capacitor value in farads. You will need to convert this to microfarad by multiplying by 1 million or to nanofarad by multiplying by 1 billion. Z is the input impedance of your amplifier. fc is the desired -3dB cutoff frequency. This filter will cause a +45° phase shift at the cutoff frequency so the phase control of the subwoofer will need to be adjusted to compensate.
More tech talk videos Danny!! I love it. I used vcap odam on xlr cables (two per side) and it's incredible and much better than the miflex I tried in that place for my nx otica roll of at 53hz. Significant sound improvement!!
Very good. We have some crossovers built out with the Vcap Odam caps that we are still burning in. When we finish getting them burned in then we'll compare them to some crossovers using Miflex caps.
@@marka9073 two caps to + and - leads and a wire for the ground connected on both ends to the correct male and female terminals. Make sure you get perfectly matched as close as possible caps for right and left channels
Interesting. The vcap website has a coupling capacitor calculator which would probably work for this application also. You give it the minus 3db point, the amplifier input impedance and it gives your cap value
Excellent video topic Danny! Could you do a video with an example of this implemented in a balanced XLR cable configuration? I'm assuming the same value cap would be used on both signal lines of the balanced line, but want to make sure. Your diy videos are so useful. Keep them coming!
You relentlessly describe how to improve mid and high end by filter and box improvements. Now, with the splitting filter: could you present how to get clean bass with minimal spectral decay and linearity from 20-80 Hz? What would be the best option: Open baffle bass, transmission-line bass, bass-reflex? Additionally: best bass placement to enhance vertical and horizontal offsets? Many thanks in advance!
I've used a Harrison Labs P Mod 100hz in line RCA filter (~85hz @ my amp's 47k ohm input), or else a Harrison Labs F Mod xover with both lo & hi pass outputs. The filters help with high-output playback, but are unnecessary for moderate playback levels. I use a 90 degree RCA splitter to switch between filtered and unfiltered.
I would like to see a video of you 5 favorite Bookshelf and 5 favorite floorstanding speakers that are not yours. Many of your videos will state how you like this speaker and others how you couldn't recommend that speaker. Many individuals are not has handy to fix a speaker, and we would like your recommendation because we trust your expertise. You could do this video annually.
I was going to get your line level high pass for my Tannoy XT8F towers, but I ended up buying a Tannoy Definition Subwoofer that has balanced high pass output. Instead of getting new Tannoy towers later, I want to take these I have to get your full out XO & cabinet upgrades & I'll drive them down myself.
My main amp is a DIY 300B, the input stage is a WE437@ but instead of a grid leak (which is a resistor to ground before the input tube), I'm using a grid choke instead, no coupling cap and inline grid stopper of 100 ohms. The DCR of the grid choke is 1.3K ohm, but it's AC impedance is 500 Meg ohm. I'm using a modified Dahlquist Low pass active, high pass passive crossover. If I use 1.3K the calcs say if I use a 1.5uf cap, my freq of roll off is just a tick over 80hz. I assume it's the DCR that needs to be used in this case, rather than a conventional "input impedance, as I have no way of physically measuring it, and there are no "specs" for this DIY amp
you can also use a multipole switch.... add a few values like 5. and aim for the middle value (based on the input impedance). then you can adjust the rolloff by the switch. its like a poor mans active :)
Wow good shit.... All these nay sayers and kids with no real experience in anything to criticize this guy.....this is what you get with seasoned and weathered real men in there field ..good job ! TEACHER.... AND MASTER....👍
I'm running DAC (Topping 90SE) RCA-->active sub (SB3000)-->monoblocks-->speakers. Can I place these filters between the sub and amps? I feel like I'm due for a more sophisticated type of bass management. If filters between sub and amp aren't advisable, any other suggestions?
I understand the distortion where the woofer has large excursion and also is expected to provide higher frequencies is called doppler distortion. This is an interesting video, but in my situation I am using a pair of GR-Research OB subs in parallel to Magnepan 2.7 QR speakers and would like to roll off the 1st octave of bass to the Maggies. What would you propose in the scenario where you are running a powered subwoofer using high powered input (speaker level) in parallel with your main speakers?
I am planning a bi-amp loudspeaker and was wondering if I should have a high roll-off filter for the woofer so the woofer never sees anything above 200Hz. Is there an in-line filter for this? A small inductor perhaps?
How about protecting the speakers from clipping and accidental square waves? The other day I turned off a component and for some reason it results in a huge and load pop from the speakers. Don’t know why it happened and the amp went into protection mode, but it was scary and could have easily damaged the speakers.
best rule of thumb is always turn on your amplifier last and always turn off your amplifier first. You can't depend on other components to not put out a large spike when powering on/off so you want to make sure your amplifier is off when turning other equipment on or off so the spike isn't amplified and sent to your speakers.
I have been a few different using M&k filters to accomplish this task. Passively rollin off below 80 hz. So far so good but those are vintage so I wonder if newer designed may do it even better?
Thanks Danny for this info. Makes lots of sense. Off the main topic, however, I can see that you have different cable lifters on your speakers wires now. Why the change? Also, why are some of the lifters not in use and just lying on the floor? Cheers.
Danny got a bucket of rebar chairs a while back and has been using them instead of the tinker toys. They're on the floor because he was recently moving them to another amp after a prototype RCA cable stopped working properly, and he just hadn't put them back up on the chairs when he filmed a couple videos on Monday.
@@les5309 They're used to suspend rebar rods within the middle of thick concrete floors. (Like the foundation of a house or commercial building) they come in a variety of sizes, shapes and materials.
Hello, just the info I was looking for. Tried the Harrison lab and it's ok. I would much prefer to do it right. Do you have the amplifier input chart posted anywhere? Thank you
I was just trying to figure out how to do something like this! Question: I don't have a separate pre-amp and power amp, just an integrated that takes RCA from my DAC and outputs straight to the speakers via high level, and to my sub via RCA pre-out. What's the best solution for high-passing my speakers in this setup without replacing my integrated with separates? Is there one?
I would recommend stereo sub's for starters. Using high level inputs on your sub's for signal. Using the same wires going to your speakers. Whatever stank your amp is sending to your speakers is the same stank you also want going to your sub's. Makes sense right. Using an RCA output (in most cases) is a mono signal, combining both the left and right. Sub's not only produce inaudible sub bass, that you feel more than hear. They also provide support for the mid bass drivers in your main speakers. Mid bass most definitely will image just as your main speakers do. In your setup you have eliminated this imaging. Effective, not achieving the sound quality you could have. Everything gets better when you incorporate the imaging of stereo sub's. Think of it as the foundation of any stereo soundscape it is rendering. Note the smaller the subwoofer driver the more articulate the bass it is capable of producing. Impact...pair of 12's absolutely. If sound quality is the main goal. High quality pair of 8" subwoofer's will do nicely. Revel performance can now be had for much less money in the Martin Logan Dynamo 400, as an example. Then it will be time for your question to be answered. I use a Wadia 151 DAC Mini...Usb and or toslink input's nothing but speaker (high level outputs) going to both main speakers and both sub's using banana's that allow another banana to plugged into them. I would also like to decrease the (low level) demands put on my main speakers. As a GR Research customer, I will contact them to see if it's possible with my setup. Contact them, they are very nice and professional. Good luck...Would love to hear what difference you heard if you try it. Steve.
thank you for this. if i cannot find the Input impedance on my amp (still looking online for the Douk audio ST-01)... are there other formulas with other values that i could calculate to see how many K-ohms my amp is able to work with? THANKS in advance
I have Klipsch rp-260f as fronts in my hometheater. Would this work for me? I have two subwoofers. I live in Sweden so i can't buy the same things you talk about.
Can someone help me understand why the phase (timing of output) of the sub is shifted +45 degrees? Is that because the sub it getting the unmodified signal and the amp is being fed a signal that now has to go through the cap and is delayed? How to think about this?
Hi Danny. Thanks for this! In my system, the entire signal path (DAC > pre-amp > power-amp) is balanced. To achieve the equivalent functionality to your single-ended example, would I just create parallel twin filter? One for each "side" of the signal? Thanks in advance for any response...
@@dannyrichie9743 Thanks for the quick reply. My Parasound A21's balanced input impedance is specified as "66k (33k per leg). What values would I use for 60Hz or 80Hz? (I switch between 2 different speakers). Perhaps if you can share the equation, I could calculate the values for myself?
Thanks Danny, is there anything like this I can do to reduce the SPL on the high frequencies? It's been suggested to me to put a 4-8ohm potentiometer in line with the tweeter to achieve that effect. If feasible I would love to know your thoughts on that.
Look for L pad type speaker attenuators, these have the benefit of maintaining fairly constant load impedance by employing combined series and parallel variable resistors.
@@dannyrichie9743 Well naturally, as long as you are versed in basic electronics, identified existing crossover alignment correctly and have access to loudspeaker measurement system. Otherwise, you can always replace rheostats with fixed value resistors, once your ears are happy with the preset values and you only need a DMM for that.
Hey Danny love your videos! I have two sound sources I would like to add these filters to, one is a external dac to amp and one is a djmixer/preamp to amp the system is two bookshelf’s and a sub hooked up to receiver used as just a amp in bypass mode (no sub out function in bypass mode) I would like to add these filters to both sound sources, will I have to make 4 of these filters? Will 2 filters between dac and amp aswell as 2 filters between dj mixer and amp work? And would I use 1 mono rca from each sound source to have sub connection from both sources Regards
In a crossover circuit, say a choke and a capacitor does it matter which way each component lies in the circuit? what if you also have a resistor in line does that matter where it is put in the circuit? Cheers
Will this highpass change phase 45 degree away from a regular analoge subwoofer filter? Phase integration with subs isnt easy without mains delay, I assume the most subs just lag 1 cycle behind the main speakers?
This type of filter will cause a +45° phase shift at the -3dB cutoff frequency. The phase control of your subwoofer will need to be adjusted to compensate.
@@nathanevans6277 Yes, but wont the +45 make things worse when if the -18db sub lowpass 3. order filter(standard) give -135°. Only way to fix that would be to add more delay so the sub matches up on cycle nr 2? My knowledge on this subject isnt good so if someone could please explain the relationship properly that would be great :)
Danny, two questions. 1. When you say octave, what are you referring to? I know what an octave is musically. I'm assuming you're talking about the low frequencies. 2. Can this be incorporated into a home theater HDMI? No turntables or cd players. We pretty much stream everything today. I understand it will be great for the subwoofer with a separate amp. Just wondering how to incorporate into the HDMI.
I use an integrated home theater AV receiver that has 7.1 pre outs but no corresponding power amp inputs. Also, my input devices - media PC, CD player, streaming device - all use HDMI outputs, so I assume an inline filter is out of the question?
E.g. if your speaker is already connected through amplifier, and the amplifier is connected to the subs High Pass Filter, will installing the In-Line Filters be redundant?
@@dannyrichie9743 good to know. Its sad cuz i have a little x-sub that you must've built over 10 years ago which does effectively roll off the bass to the speakers. Love its bass management. I'll have to get myself an in-line filter and hear the difference.
@@Jonathan-ff4wo Those X-subs use a 100uF electrolytic cap as a high pass filter (if I remember correctly). So getting that out of the signal path should open everything up significantly.
I'm running a little EL84 vacuum tube integrated amp with the volume turned all the way up and I'm running a preamp into one of its line level inputs would I put this or could I put this filter before that line level input?
Can this filter be sort of a two-step filter in that below 20 Hertz it rolls off really steeply for subsonics? Some of my records cause the woofers to just thump with no sound My preamp doesn't have a subsonic filter
Can someone explain how this is different than using the line level inputs on my (powered) sub and letting the onboard high-pass filter out to the speakers do the low frequency roll-off?
If your sub has a cheap electroletic cap for that filter, this is an upgrade. Look for GR Research vid on Rythmik sub setup. He covers this. My pre amp has 2 amp outs so one can go to sub. The 2nd with this filter inline to amp for main speakers.
Canton had something called DC, Displacement Control, in their speakers for a while, an electrolytic capacitor, 1000µF, with a ferrite bell core drossel. Ain´t got a clue how they succeeded to sell it.
Thanks so much for this information! Super helpful. Can you do a similar talk about low-pass filters? I'm asking because I have several passive subs that I'd love to be able to use them to roll off the high end. Adjustable would be great, but a single value would be great. Thank you!
It is expensive to make good low pass passive filters. It is not much more cost to buy a good subwoofer plate amp and then you have the flexibility of output level, crossover point, and often phase too.
Can someone link to more info on this? eg: how much power is required for that sub bass region? How much does that free up a speaker to play louder? how much more head room will an amp have? is there a curve graph on this?
I have a question. What is the highest crossover point where it would make most sense to use an in line filter? I'm wondering about something in the order of ~500Hz?
It's very dependant on your subwoofers. Many may only play as high as 120-160Hz, some can play up to 200/300Hz. But generally, subs don't make for good woofers above 100-150Hz. They tend to be easier to localize above 100hz, and it becomes more difficult to adjust the phase to cleanly match them. So a -3dB of 125Hz, or lower, is the about as far as I would go. Ideally, I wouldn't roll off above 75-85Hz for most speakers, if possible. It will give you a lot more headroom, (up to 4x at 80Hz) without completely losing all of your bass output. For a really small desktop speaker, you can get away with ~100-150Hz.
@@hoth2112 oh hi! I've seen you from lurking on the audio circle forums. I understand this. My question is not regarding the quality of subwoofers at higher frequencies, but rather, what is the maximum frequency at which it makes more sense to use an in-line filter over a normal high pass filter in the crossover?
@@bryanbassett2110 100-125Hz at most. Any higer, and you're getting into values that are well into the low nanofarad ranges, which are very hard to come by in good quality options.
So... im using diy amps.. the Nelson pass amp camp amps... how do I measure the input impedence of my amplifiers... im running then in mono with xlr cable connections Never mind... its actually on their website... 10kohm.
But Danny - aren't you shifting the phase of the music signal going to the amp by 180 degrees? Shouldn't you flip the positive and negative at the speaker output of the main amp to compensate?
Of course the coupling caps in the amps and pre-amp shift the phase, but they are designed internally to take that into account. Any pre-amp or amplifier designer is not expecting to have a cap in the path between that inverting the phase by 180 degrees. What Synthesis did in their commercially designed passive filter was to series the caps (cutting the overall uF by half so each cap was double what they wanted) to keep the +ve and -ve music swings out of the preamp, the same as with or without their passive crossover in the path between the pre and power. Some may argue it makes no audible difference, but some philes are sticklers for this, and insist they can hear the difference and that it be correct. I have never tried experimenting - but it is worth considering.
The coupling caps often found in pre and power amps are there to block DC. The cutoff frequency is usually set at only a couple of hertz. This will result in virtually no phase shift within the audio band. Using a capacitor to roll off the bottom end will result in a phase shift within the audio band as the cutoff frequency will be within the band. A single capacitor will introduce a maximum phase shift of +90° but this won't happen until the signal has been fully attenuated so is moot. Luckily human hearing is not very sensitive to phase shifts at low frequency. It is most sensitive in the frequency range where most tweeters cross to the midrange. The crossovers used here are normally higher order and introduce much more phase shift. The phase shift at the cutoff frequency of one of these in-line filters will be +45° and can be compensated for by adjusting the phase control of the subwoofer. The question is "is this phrase shift and the inevitable signal degradation incurred by passing the signal through the capacitor outweighed by the reduction in distortion of the driver?" This will be system dependent so is a try it and see. The one system that I have tried this on sounded much better with the bottom end of the main speakers rolled off.
What equation do you use to calculate the value of the cap? As first order filter, My amp has a 100k ohms impedance, I would like to filter out signal over 25 kKz, on a balance cable (a special application). Wy are polycap better then electrolytic caps?😊
Good question, are poly caps really better? Can't really say that they are, I've used both, sonically their pretty well the same if their the same values, but durability wise I'd say the poly caps will hold up better as I've seen 30 year old electros swell and sometimes burst in several speakers over the years, but I'd say the real difference is that, just my opinion though, electro caps u maybe 30 years out of em, poly caps maybe 40+ years, but I'm not a certified expert, but seems to me it's cheaper just to change your electrolytic caps out every 10 years or so to be safe and save some dough over polys, many decisions, just up to the owner I guess.
@@JukeboxAlley The differences in sound quality between electrolytic caps and poly caps can be substantial. Even the differences between various types of poly caps can be surprisingly clear.
@@dannyrichie9743 i have heard some sound different on top end/midrange setups, but on the woofer section if just using for low end roll off etc. I don't think it's that critical of a difference between those types myself for analytical listening (if just for the bottom end), but I can tell a difference on the top end with some, just depends if you want to spend a little more to squeeze every bit you can out of the drivers I suppose.
So what if your integrated amplifier has high pass capability and allows you high pass your speakers at selected hz, is this as good as what your doing?
Danny, I have to say that your knowledge of the intricacies of the audio signal is nothing short of astounding! Thank you for sharing it.
As a friend always say:« Your light doesn't dim when you ignite someone else's flame. It just makes the world shine that much brighter...»😉
👍 I have been doing this since the 80’s both for home and restaurant / bar systems. I also just do it inside the amp, less cables is always good.
Thats interesting, so basically you implement the caps in the amp directly after the pre inputs? That sounds even less hard an no need of boxes etc…Its a trade off I understand and if you change speaker you have to adjust but it seems line a good option? Anything I’m missing here?
I didn’t think when I brought up this topic to you using electrolytic in line I didn’t think it was gonna lead to this but it’s very cool
This is one of your best videos yet. Thanks Danny!
Without learning, life becomes boring. Thank-you Danny 😃
I was on a mission today to look up what was the best way to do this. For some reason I checked your channel today and there it was. Karma? Maybe, but a big thanks for this vid ! You saved me a bunch of searching and in 15 min you clearly explained it all clearly and concisely. Love your channel ! Hoping to build one of your speaker kits very soon.
I HAVE LEARNED ALOT..and ive discovered something never discussed.. soon ill have enough info so I can give correct presentation.. of my discovery..thanks danny.. you already know what ive learned.
Danny is an amazing teacher. Will definitely do this 👍
Awesome informative tech talk video. More please.
Education and educational material is definitely your wheelhouse. Thank you so much I will be attempting this immediately.
Fascinating subject matter Danny. Thanks!
I REALLY like your content. You provide a service. I should send you a t-shirt one of these days.
I often wear t-shirts that people send in.
Great video. So much information in such a short video.!
This will work perfect with my Kef 101's and my Kef B139 woofers.
Thanks for providing this excellent advice. I am keen to try this out.
Thank you Danny, i've been wanting to know this since you mentioned these filters a few years ago. Cheers.
Fantastic advice, thank you Danny!
Thanks for sharing with us Danny.
Thank you for answering the question I thought about, but was afraid to ask.
I asked a silly question before end of video which was answered ! Thanks Danny, this is super informative!
Thanks for providing this amazing information for free!
Fantastic stuff here! I'd been researching low cost & DIY active x-overs, this is no doubt the most cost effective way to go!
Thanks Danny, I was looking forward to this video
Very interesting. Thanks Danny
Richard Vandersteen has been advocating the use of high pass filters along with his subs for decades. Good video!
This video is awesome. Especially when you have a subwoofer in your system taking care of the deeper frequencies, you gotta have a high-pass filter for your stereo speakers. It's a bummer that some opinion-maker people in this industry think a subwoofer just need to run in parallel with your small speakers ending up struggling with the lower bass causing a lot of distortion. Especially high-end amplifier companies lack proper solutions for this issue and will often just tell you to connect your subwoofer on the speaker terminals to your stereo speakers completely messing up the lower bass quality, especially at higher volume.
Good info. Thanks for sharing.
Love your vids
Still savin for the open baffles behind ya! Well the shorter ones. Also learning about even odd order ect ect. BIG thanks for this one, working on sketching out a crossover system, not easy.
Yet an other reason to buy a vintage amplifier. I just have to push the 70 Hz filter button.
Nice and informative video. Those little bookshelfs you've got there must sound really nice with inline filter and a separate subwoofer.
I've been following you for a long time and this is the best iteration of those giant killers.
It would be nice if you would extend the video and talk about active filters, op amps, pro's and con's (figure it's going to be mostly cons), since you mentioned active circuitry.
Cheers,
Stefan
Great Video Danny, thanks for sharing your knowledge.
I ordered 2 x clarity caps esa 0.047uf crossing at 72hz, took an old decent quality rca cable, cut in half, did the same with a subwoofer cable then drilled 6 holes in a sturdy black VHS tape case.
I then threaded the cables through the snuggly fitting holes, stripped the wire then soldered everything together, snapped the case shut and eureka, a fully functioning high pass filter at minimum cost and minimal disruption to the signal path.
I hope this helps someone else, shame I can't share the photos
Thank you for a very helpful video
Yep!
Rolling off the lowest octave improves every aspect of the mid/woofer's performance.
Transient response, vocal clarity, imaging, soundstage, dynamic range...
I’d strongly recommend using a *metal* project box for adequate shielding.
I really like your LGKs!
One of my little dreams …
If you want to work out the value of capacitor for a given input impedance and -3dB point use this equation,
C=1/(2πZfc)
Where C is the capacitor value in farads. You will need to convert this to microfarad by multiplying by 1 million or to nanofarad by multiplying by 1 billion.
Z is the input impedance of your amplifier.
fc is the desired -3dB cutoff frequency.
This filter will cause a +45° phase shift at the cutoff frequency so the phase control of the subwoofer will need to be adjusted to compensate.
Thanks for the notification about the variance in phase and for the formula for calculation!✌
thanks for this video
More tech talk videos Danny!! I love it.
I used vcap odam on xlr cables (two per side) and it's incredible and much better than the miflex I tried in that place for my nx otica roll of at 53hz. Significant sound improvement!!
Very good. We have some crossovers built out with the Vcap Odam caps that we are still burning in. When we finish getting them burned in then we'll compare them to some crossovers using Miflex caps.
Can you show me how you did that for xlr cables?
@@joelrunyan1608 XLR cables require a pair of matched caps. One is used on each positive leg.
@@dannyrichie9743 not certain what that would physically look like to get it done for xlr cables.
@@marka9073 two caps to + and - leads and a wire for the ground connected on both ends to the correct male and female terminals. Make sure you get perfectly matched as close as possible caps for right and left channels
Interesting. The vcap website has a coupling capacitor calculator which would probably work for this application also. You give it the minus 3db point, the amplifier input impedance and it gives your cap value
Thanks for the tip. I looked it up, and yes indeed, it is spot on for this application
Excellent video topic Danny! Could you do a video with an example of this implemented in a balanced XLR cable configuration? I'm assuming the same value cap would be used on both signal lines of the balanced line, but want to make sure. Your diy videos are so useful. Keep them coming!
You are correct.
I do not see the sheet with the values shown in the video?
Exactly what I wish to have instead of active ic based treble bass controls🎉🎉🎉
You relentlessly describe how to improve mid and high end by filter and box improvements. Now, with the splitting filter: could you present how to get clean bass with minimal spectral decay and linearity from 20-80 Hz? What would be the best option: Open baffle bass, transmission-line bass, bass-reflex? Additionally: best bass placement to enhance vertical and horizontal offsets? Many thanks in advance!
When it comes to best bass response I am all in for open baffle. It will always minimize room gains and room boom.
I've used a Harrison Labs P Mod 100hz in line RCA filter (~85hz @ my amp's 47k ohm input), or else a Harrison Labs F Mod xover with both lo & hi pass outputs. The filters help with high-output playback, but are unnecessary for moderate playback levels. I use a 90 degree RCA splitter to switch between filtered and unfiltered.
Spent a few months in Wichita Falls, Sheppard AFB to be precise. One of the coldest winters I’ve experienced. Circa 85’. Brrr
Thanks! 'Le Clanche' signal path Tin/Polyprops look a really good option on a budget...(?)
Haha
I was literally on the GR-Research website last night looking for these.
I wish I could figure out a way to have some good quality ones made.
Thanks Danny. Can you post that value sheet on the audiocircle thread you link to? Thanks
Try this one: www.learningaboutelectronics.com/Articles/High-pass-filter-calculator.php#answer1
I wish you would do another discussion on open baffle speakers.
Check my videos. I did four videos on that subject.
I would like to see a video of you 5 favorite Bookshelf and 5 favorite floorstanding speakers that are not yours. Many of your videos will state how you like this speaker and others how you couldn't recommend that speaker. Many individuals are not has handy to fix a speaker, and we would like your recommendation because we trust your expertise.
You could do this video annually.
I was going to get your line level high pass for my Tannoy XT8F towers, but I ended up buying a Tannoy Definition Subwoofer that has balanced high pass output.
Instead of getting new Tannoy towers later, I want to take these I have to get your full out XO & cabinet upgrades & I'll drive them down myself.
Careful, those high pass filters built into those amps are usually electrolytic caps. So the quality level is very poor.
My main amp is a DIY 300B, the input stage is a WE437@ but instead of a grid leak (which is a resistor to ground before the input tube), I'm using a grid choke instead, no coupling cap and inline grid stopper of 100 ohms. The DCR of the grid choke is 1.3K ohm, but it's AC impedance is 500 Meg ohm. I'm using a modified Dahlquist Low pass active, high pass passive crossover. If I use 1.3K the calcs say if I use a 1.5uf cap, my freq of roll off is just a tick over 80hz. I assume it's the DCR that needs to be used in this case, rather than a conventional "input impedance, as I have no way of physically measuring it, and there are no "specs" for this DIY amp
you can also use a multipole switch.... add a few values like 5. and aim for the middle value (based on the input impedance). then you can adjust the rolloff by the switch. its like a poor mans active :)
Wow good shit.... All these nay sayers and kids with no real experience in anything to criticize this guy.....this is what you get with seasoned and weathered real men in there field ..good job ! TEACHER.... AND MASTER....👍
This would make nice kits to sell...
If I could just find top level RCA ends that didn't cost a fortune...
I'm running DAC (Topping 90SE) RCA-->active sub (SB3000)-->monoblocks-->speakers. Can I place these filters between the sub and amps? I feel like I'm due for a more sophisticated type of bass management. If filters between sub and amp aren't advisable, any other suggestions?
I understand the distortion where the woofer has large excursion and also is expected to provide higher frequencies is called doppler distortion.
This is an interesting video, but in my situation I am using a pair of GR-Research OB subs in parallel to Magnepan 2.7 QR speakers and would like to roll off the 1st octave of bass to the Maggies. What would you propose in the scenario where you are running a powered subwoofer using high powered input (speaker level) in parallel with your main speakers?
Then the inline filter I show in this video would be ideal.
I am planning a bi-amp loudspeaker and was wondering if I should have a high roll-off filter for the woofer so the woofer never sees anything above 200Hz. Is there an in-line filter for this? A small inductor perhaps?
Follow what I cover regarding bi-amping in this one: czcams.com/video/908BWw1Bx4U/video.html
Danny plays chess while most others are learning to play checkers.
How about protecting the speakers from clipping and accidental square waves?
The other day I turned off a component and for some reason it results in a huge and load pop from the speakers. Don’t know why it happened and the amp went into protection mode, but it was scary and could have easily damaged the speakers.
best rule of thumb is always turn on your amplifier last and always turn off your amplifier first.
You can't depend on other components to not put out a large spike when powering on/off so you want to make sure your amplifier is off when turning other equipment on or off so the spike isn't amplified and sent to your speakers.
Do you plan on selling completed in line filters? Or suggestions for a high quality completed version?
Not currently.
I have been a few different using M&k filters to accomplish this task. Passively rollin off below 80 hz. So far so good but those are vintage so I wonder if newer designed may do it even better?
Thanks Danny for this info. Makes lots of sense. Off the main topic, however, I can see that you have different cable lifters on your speakers wires now. Why the change? Also, why are some of the lifters not in use and just lying on the floor? Cheers.
Danny got a bucket of rebar chairs a while back and has been using them instead of the tinker toys.
They're on the floor because he was recently moving them to another amp after a prototype RCA cable stopped working properly, and he just hadn't put them back up on the chairs when he filmed a couple videos on Monday.
@@hoth2112 Thank you. I'm not familiar with rebar chairs; could you explain those items?
@@les5309 They're used to suspend rebar rods within the middle of thick concrete floors. (Like the foundation of a house or commercial building) they come in a variety of sizes, shapes and materials.
@@hoth2112 Many thanks.
Hello, just the info I was looking for. Tried the Harrison lab and it's ok. I would much prefer to do it right. Do you have the amplifier input chart posted anywhere?
Thank you
I was just trying to figure out how to do something like this! Question: I don't have a separate pre-amp and power amp, just an integrated that takes RCA from my DAC and outputs straight to the speakers via high level, and to my sub via RCA pre-out. What's the best solution for high-passing my speakers in this setup without replacing my integrated with separates? Is there one?
I would recommend stereo sub's for starters. Using high level inputs on your sub's for signal. Using the same wires going to your speakers. Whatever stank your amp is sending to your speakers is the same stank you also want going to your sub's. Makes sense right. Using an RCA output (in most cases) is a mono signal, combining both the left and right. Sub's not only produce inaudible sub bass, that you feel more than hear. They also provide support for the mid bass drivers in your main speakers. Mid bass most definitely will image just as your main speakers do. In your setup you have eliminated this imaging. Effective, not achieving the sound quality you could have. Everything gets better when you incorporate the imaging of stereo sub's. Think of it as the foundation of any stereo soundscape it is rendering. Note the smaller the subwoofer driver the more articulate the bass it is capable of producing. Impact...pair of 12's absolutely. If sound quality is the main goal. High quality pair of 8" subwoofer's will do nicely. Revel performance can now be had for much less money in the Martin Logan Dynamo 400, as an example. Then it will be time for your question to be answered. I use a Wadia 151 DAC Mini...Usb and or toslink input's nothing but speaker (high level outputs) going to both main speakers and both sub's using banana's that allow another banana to plugged into them. I would also like to decrease the (low level) demands put on my main speakers. As a GR Research customer, I will contact them to see if it's possible with my setup. Contact them, they are very nice and professional. Good luck...Would love to hear what difference you heard if you try it. Steve.
what if you have a 2.5 way speaker? treble and 8 inch and 10 inch bass/sub and you want to remove everything below 100hz on 8 inch speaker?
Then something like I described might work really well for you.
thank you for this.
if i cannot find the Input impedance on my amp (still looking online for the Douk audio ST-01)... are there other formulas with other values that i could calculate to see how many K-ohms my amp is able to work with?
THANKS in advance
I have Klipsch rp-260f as fronts in my hometheater. Would this work for me? I have two subwoofers. I live in Sweden so i can't buy the same things you talk about.
Can someone help me understand why the phase (timing of output) of the sub is shifted +45 degrees? Is that because the sub it getting the unmodified signal and the amp is being fed a signal that now has to go through the cap and is delayed? How to think about this?
Hi Danny. Thanks for this! In my system, the entire signal path (DAC > pre-amp > power-amp) is balanced. To achieve the equivalent functionality to your single-ended example, would I just create parallel twin filter? One for each "side" of the signal? Thanks in advance for any response...
Hi, I have the same question!
Yes, in that case you need two caps per channel with one on each positive leg.
@@dannyrichie9743 Thanks for the quick reply. My Parasound A21's balanced input impedance is specified as "66k (33k per leg). What values would I use for 60Hz or 80Hz? (I switch between 2 different speakers). Perhaps if you can share the equation, I could calculate the values for myself?
@@michaelsparrow4798 See this link: www.learningaboutelectronics.com/Articles/High-pass-filter-calculator.php#answer1
@@michaelsparrow4798 I posted the equation earlier in the comments. I guessed that it was a question that quite a few people would ask.
Thanks Danny, is there anything like this I can do to reduce the SPL on the high frequencies? It's been suggested to me to put a 4-8ohm potentiometer in line with the tweeter to achieve that effect. If feasible I would love to know your thoughts on that.
Look for L pad type speaker attenuators, these have the benefit of maintaining fairly constant load impedance by employing combined series and parallel variable resistors.
Keep parts like potentiometers out of the signal path. I bet your tweeter already has some resistors on them. Just adjust the values.
@@dannyrichie9743 thanks!
@@dannyrichie9743 Well naturally, as long as you are versed in basic electronics, identified existing crossover alignment correctly and have access to loudspeaker measurement system. Otherwise, you can always replace rheostats with fixed value resistors, once your ears are happy with the preset values and you only need a DMM for that.
You da man Dan!
How does output impeadance of the source device affect this?
I have devices that range from 20-500Ω
The output impedance of the source will have no effect.
It is only the input impedance of your power amplifier that is important.
Will this help with lower db speakers (85-88) to be driven by lower watt amps ie: tube amps?
It will free up a little amp power.
👍🙏
Hey Danny love your videos!
I have two sound sources I would like to add these filters to, one is a external dac to amp and one is a djmixer/preamp to amp
the system is two bookshelf’s and a sub hooked up to receiver used as just a amp in bypass mode (no sub out function in bypass mode)
I would like to add these filters to both sound sources, will I have to make 4 of these filters?
Will 2 filters between dac and amp aswell as 2 filters between dj mixer and amp work?
And would I use 1 mono rca from each sound source to have sub connection from both sources
Regards
Are you using the same amps?
In a crossover circuit, say a choke and a capacitor does it matter which way each component lies in the circuit? what if you also have a resistor in line does that matter where it is put in the circuit? Cheers
In some cases which part comes first is imperative and in some areas of the circuit the order of some parts doesn't matter.
Will this highpass change phase 45 degree away from a regular analoge subwoofer filter? Phase integration with subs isnt easy without mains delay, I assume the most subs just lag 1 cycle behind the main speakers?
I would also like to know the answer to this
This type of filter will cause a +45° phase shift at the -3dB cutoff frequency. The phase control of your subwoofer will need to be adjusted to compensate.
@@nathanevans6277 Yes, but wont the +45 make things worse when if the -18db sub lowpass 3. order filter(standard) give -135°. Only way to fix that would be to add more delay so the sub matches up on cycle nr 2? My knowledge on this subject isnt good so if someone could please explain the relationship properly that would be great :)
Danny, two questions.
1. When you say octave, what are you referring to? I know what an octave is musically. I'm assuming you're talking about the low frequencies.
2. Can this be incorporated into a home theater HDMI? No turntables or cd players. We pretty much stream everything today. I understand it will be great for the subwoofer with a separate amp. Just wondering how to incorporate into the HDMI.
The first octave (that we can hear) is 20Hz to 40Hz. The second is 40Hz to 80Hz.
This only works with a separate amplifier.
I use an integrated home theater AV receiver that has 7.1 pre outs but no corresponding power amp inputs. Also, my input devices - media PC, CD player, streaming device - all use HDMI outputs, so I assume an inline filter is out of the question?
That is correct.
If I have an integrated amplifier, would I have to install this between my source component and the integrated amp input?
You can.
Thanks, Beginner, I was wondering the same!
Is there some way to measure the input impedance? Like with a multimeter or something? I cant find it listed for my amp anywhere.
Not easily. It is best to contact the maker of the amplifier to get that information.
how would you use the bass roll off on balanced cables ?
You will need a matched cap for each positive leg.
E.g. if your speaker is already connected through amplifier, and the amplifier is connected to the subs High Pass Filter, will installing the In-Line Filters be redundant?
Do not use a high pass filter built into a subwoofer plate amp. Those are typically just an electrolytic cap.
@@dannyrichie9743 good to know. Its sad cuz i have a little x-sub that you must've built over 10 years ago which does effectively roll off the bass to the speakers. Love its bass management. I'll have to get myself an in-line filter and hear the difference.
@@dannyrichie9743 would you say there are exceptions to this though? ie REL and Rythmik?
@@Jonathan-ff4wo Those X-subs use a 100uF electrolytic cap as a high pass filter (if I remember correctly). So getting that out of the signal path should open everything up significantly.
@@JC-lk3oy We use the Rythmik servo amps. Using any internal high pass filter in those amps are not recommended.
I'm running a little EL84 vacuum tube integrated amp with the volume turned all the way up and I'm running a preamp into one of its line level inputs would I put this or could I put this filter before that line level input?
Yes you can.
Can this filter be sort of a two-step filter in that below 20 Hertz it rolls off really steeply for subsonics? Some of my records cause the woofers to just thump with no sound My preamp doesn't have a subsonic filter
This is a high pass filter. It will roll off the lows with a low order slope. So it will help with your issue.
If you cut low frequencies before they enter the amp, doesnt that mean any sub that you use wont work?
Can someone explain how this is different than using the line level inputs on my (powered) sub and letting the onboard high-pass filter out to the speakers do the low frequency roll-off?
If your sub has a cheap electroletic cap for that filter, this is an upgrade. Look for GR Research vid on Rythmik sub setup. He covers this.
My pre amp has 2 amp outs so one can go to sub. The 2nd with this filter inline to amp for main speakers.
Canton had something called DC, Displacement Control, in their speakers for a while, an electrolytic capacitor, 1000µF, with a ferrite bell core drossel. Ain´t got a clue how they succeeded to sell it.
That is the absolute worst way to filter off the lows.
Thanks so much for this information! Super helpful. Can you do a similar talk about low-pass filters? I'm asking because I have several passive subs that I'd love to be able to use them to roll off the high end. Adjustable would be great, but a single value would be great. Thank you!
It is expensive to make good low pass passive filters. It is not much more cost to buy a good subwoofer plate amp and then you have the flexibility of output level, crossover point, and often phase too.
Can someone link to more info on this? eg: how much power is required for that sub bass region? How much does that free up a speaker to play louder? how much more head room will an amp have? is there a curve graph on this?
would I look up the Power to Db ratio table, then compare that to the Fletcher Munson curve?
A handy rule of thumb for music is that roughly half the power is consumed by frequencies up to 180hz, and the rest is above 180hz.
I'm running pass labs aleph j monos. Impedes of 242k. Driving quad esl988. Any suggestion on cap values? Thank you.
Also using rythmik f12 subs. Thanx
I have a question. What is the highest crossover point where it would make most sense to use an in line filter? I'm wondering about something in the order of ~500Hz?
i would say 200hz if you got stereo subwoofers that play nice that high. i have used 200hz before and its great.
It's very dependant on your subwoofers. Many may only play as high as 120-160Hz, some can play up to 200/300Hz. But generally, subs don't make for good woofers above 100-150Hz. They tend to be easier to localize above 100hz, and it becomes more difficult to adjust the phase to cleanly match them. So a -3dB of 125Hz, or lower, is the about as far as I would go. Ideally, I wouldn't roll off above 75-85Hz for most speakers, if possible. It will give you a lot more headroom, (up to 4x at 80Hz) without completely losing all of your bass output. For a really small desktop speaker, you can get away with ~100-150Hz.
@@hoth2112 oh hi! I've seen you from lurking on the audio circle forums.
I understand this. My question is not regarding the quality of subwoofers at higher frequencies, but rather, what is the maximum frequency at which it makes more sense to use an in-line filter over a normal high pass filter in the crossover?
@@bryanbassett2110 100-125Hz at most. Any higer, and you're getting into values that are well into the low nanofarad ranges, which are very hard to come by in good quality options.
@@hoth2112 good to know! Appreciate it
So... im using diy amps.. the Nelson pass amp camp amps... how do I measure the input impedence of my amplifiers... im running then in mono with xlr cable connections
Never mind... its actually on their website... 10kohm.
But Danny - aren't you shifting the phase of the music signal going to the amp by 180 degrees? Shouldn't you flip the positive and negative at the speaker output of the main amp to compensate?
Is it shifted by the output coupling caps in the pre-amp and input coupling caps in the amp?
The filter will shift phase by +45° at the cutoff frequency. The phase control of your subwoofer will need to be adjusted to compensate.
Of course the coupling caps in the amps and pre-amp shift the phase, but they are designed internally to take that into account. Any pre-amp or amplifier designer is not expecting to have a cap in the path between that inverting the phase by 180 degrees. What Synthesis did in their commercially designed passive filter was to series the caps (cutting the overall uF by half so each cap was double what they wanted) to keep the +ve and -ve music swings out of the preamp, the same as with or without their passive crossover in the path between the pre and power. Some may argue it makes no audible difference, but some philes are sticklers for this, and insist they can hear the difference and that it be correct. I have never tried experimenting - but it is worth considering.
The coupling caps often found in pre and power amps are there to block DC. The cutoff frequency is usually set at only a couple of hertz. This will result in virtually no phase shift within the audio band. Using a capacitor to roll off the bottom end will result in a phase shift within the audio band as the cutoff frequency will be within the band. A single capacitor will introduce a maximum phase shift of +90° but this won't happen until the signal has been fully attenuated so is moot. Luckily human hearing is not very sensitive to phase shifts at low frequency. It is most sensitive in the frequency range where most tweeters cross to the midrange. The crossovers used here are normally higher order and introduce much more phase shift.
The phase shift at the cutoff frequency of one of these in-line filters will be +45° and can be compensated for by adjusting the phase control of the subwoofer.
The question is "is this phrase shift and the inevitable signal degradation incurred by passing the signal through the capacitor outweighed by the reduction in distortion of the driver?"
This will be system dependent so is a try it and see.
The one system that I have tried this on sounded much better with the bottom end of the main speakers rolled off.
@@nathanevans6277 You are correct.
What equation do you use to calculate the value of the cap? As first order filter, My amp has a 100k ohms impedance, I would like to filter out signal over 25 kKz, on a balance cable (a special application). Wy are polycap better then electrolytic caps?😊
Try this one: www.learningaboutelectronics.com/Articles/High-pass-filter-calculator.php#answer1
Good question, are poly caps really better? Can't really say that they are, I've used both, sonically their pretty well the same if their the same values, but durability wise I'd say the poly caps will hold up better as I've seen 30 year old electros swell and sometimes burst in several speakers over the years, but I'd say the real difference is that, just my opinion though, electro caps u maybe 30 years out of em, poly caps maybe 40+ years, but I'm not a certified expert, but seems to me it's cheaper just to change your electrolytic caps out every 10 years or so to be safe and save some dough over polys, many decisions, just up to the owner I guess.
@@JukeboxAlley The differences in sound quality between electrolytic caps and poly caps can be substantial. Even the differences between various types of poly caps can be surprisingly clear.
@@dannyrichie9743 i have heard some sound different on top end/midrange setups, but on the woofer section if just using for low end roll off etc. I don't think it's that critical of a difference between those types myself for analytical listening (if just for the bottom end), but I can tell a difference on the top end with some, just depends if you want to spend a little more to squeeze every bit you can out of the drivers I suppose.
@@JukeboxAlley I would agree with that observation.
Can you just roll off the lows by setting your receiver to not send those lows to the amp then to your speakers.
Is this like crossing over to the sub woofer at 80 to 100?
No, this is showing you how to build a high pass filter. Where the slope starts depends on the cap value used and input impedance of your amp.
Can you make these for xlr cables?
Yes, it just requires you to use a pair of matched caps on each positive leg.
So what if your integrated amplifier has high pass capability and allows you high pass your speakers at selected hz, is this as good as what your doing?
That's great.