Why a Flat Frequency Response Makes Sense
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- Äas pĆidĂĄn 24. 03. 2021
- In this video, I talk about why a flat on-axis response for a speaker is best. The speaker should also be well-behaved off-axis. This is not the same as your system measuring flat at your listening position or using flat as your target curve in your room correction DSP. Flat at your listening position does sound like crap. If you take a well-behaved off-axis speaker that has a flat frequency response on-axis, in a typical room, you can expect the measurement in your listening position to have a slight downward tilt where the bass is higher than the treble.
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There's something you missed here about the chain. I have sat in studios with numerous bands now. The end product (post mastering) sounds nothing like what i heard in the studio. All that a flat response in a well treated room may give me is a true representation of the abomination of a recording i bought. Why would i even give a ratsass about flat at this point? I'll color it up to how it sounds best to my ears.
Circle of Confusion: rock songs in the 70âs were often mastered to sound good for playback on crappy car radios so you can imagine how it would not be great on a home system
Thankfully we have technology to remaster them.
@@Clobercow1 mastering cant do much compared to recording/mixing
And when compared to the modern, compressed production, it sounds wonderful.
@@lextr3110 When a record company says something is "remastered" they typically mean it has been "remixed" as well. Unfortunately, "remixed" started to mean something different (rap and electronica) right around the time these companies started remixing recordings. I believe they just call it all remastering now to avoid confusion.
I'm a photographer. In camera terms, it would be like having a digital camera that doesn't produce accurate colors. For example, let's say you had a camera that boosted reds, produced dull blues, and had yellows that had a greenish tint. You want a camera that captures accurate colors as a baseline
Then you can tweak it from there if you like.
I always appreciated the similarities between photography and mixing
YES! Sorry for being so excited but I just happened to look and boom, first to comment đČ Anyway Iâm a big fan of flat FR with highly controlled directivity for home theater use! As far as tilting isnât that whatâs DIRAC made to do?
Early bird. DIRAC has a downward tilt to it's default target curve, but you can customize the target or your liking.
I completely agree with this. and imagine after finally getting your main speakers sounding good in YOUR room. then adding an subwoofer and it changing the bass phase or polarity and having to fight to get them all in tune with each other. You could be fighting with this for months before you get things sounding properly. But yes, get your flat frequency response first. Then you are allowed to give them some "personality" with your EQ based on what you are watching or listening to. also you have to think about sound stage and how far apart the speakers need to be from each other and if that will effect the placement of your subwoofer or if your room will allow it. Great video!
Regarding adding subs, that's what I like so much about DIRAC. It does a great job doing what you said about blending them with the mains. Better than what I can do manually imo.
oh this is a good one, I like this type of material to go along with the audiophile terms you guys did.
I think it's also helpful to know how the room impacts the frequency response if you measure at the tweeter speaker or at the sweet spot. Also you got frequency response for headphones and IEMs that can be flat but don't actually look "flat" due to ear gain or the way the ear hears sound depending upon placement of the transducer. Then you've preference curves like the harman target(s) where they have survey what people like or at least the perception of a sound signature people think they prefer. Typically a boost at the bottom end/base shelf and sweet spot in the mids and a detailed yet not spikey treble are preferred but not necessarily "neutral or flat".
Audio engineers and recording studios also don't make music that's intended to be heard at a reference level. They produce music and content to be heard on a general variety of speakers and headphones. There's subjectivity to your own audio setup ~
Flat is a great palette from which to add color. A canvas ripped in the middle is always going to be missing a chunk. Good vid.
Great stuff, Joe. Getting the basics right. Then tune to taste and circumstances, in some cases. Lots of people are going to rethink their priorities.
Great video! Iâm loving your content man!!! I have speakers that I believe arenât exactly flat, and I have eqâd them to flat with audessy multi eq xt32, and the flat response sounds awesome to me!!! I know, itâs probably better to get speakers that are flat in the first place, but this saved me money and I love the sound!! So much clarity and it sounds so realistic!
Yes Dr. Tooleâs book is a must read for anyone who is interested in learning about the science for good sound!
This concept is so important. Itâs the basis of being able to assemble a system with complimentary pieces, ultimately resulting in a system with good synergy. Understanding the sonic character of how the pieces fit together, and your room, will give you a âbetterâ system.
Thanks Joe.
Now i have my head around this complex topic, you explanation was very informative and easy to understand, great job đđ
You're very welcome!
It's basically the same thing people do with color when they edit videos or pictures. Get it to look/sound natural first and then add extra effects to make it enjoyable to listen/or to look. You just get more consistent results this way.
Yeah, you can liken it to RAW vs JPEG photo editing.
If you have a non-neutral speaker (JPEG), you may like the default adjustments, but itâs very difficult to make changes after that look good.
If you have a neutral speaker (RAW), you have a ton of range if you want to apply DSP in the bass or adjust the treble tilt.
That's exactly what people do when color correcting. They get it right first, then they add their flavor after.
Plot twist - our ears are not microphones, the ears and ear canals boost certain frequencies, and there's the brain interprating it all...
Well said Joe. And yes, I don't think speaker reviews address off-axis response enough (vertically and horizontally). Obviously, a lot of reviewers don't have the capability to measure such things, but I think these are helpful metrics to have.
I'm still learning a lot about speakers, so thank you for these great videos!
Great video man. It would be cool to do a video where you would move a speaker to different parts of the room and we could listen for the differences. Even off axis listening would be cool. Like what does it sound like if youâre standing up vs sitting.
Lived this scenario exactly this week. Got a new dac/amp for home office. Sounded a little light with just desktop speakers so added a sub that I had been using in my bedroom. In the bedroom it got boomy even at the lowest power setting. In the office I could barely hear it at full power. I thought it was something wrong w/ the new amp until I stood up and walked out of the room. From 3 feet away I couldn't hear it. From 10 feet away it thumped my chest. Room acoustics, speaker position and listening position can totally change a speaker.
Great video. Itâs interesting to hear the different camps on âartist intentionâ and flat frequency response. Iâm on the Itâs just music đ¶ đ” đŒ camp. If it makes me dance, cry, laugh, or stare into the void because of imaging and soundstage, then itâs the âbestâ speaker. If not, then on to the next home audition. Itâs all an illusion. And itâs wonderful!!!! Enjoy the music!!!
@@Jtzkb letâs not forget that âoriginalâ and âartist intentâ are also illusions and are words used by audio manufacturers to sell us their products. Seldom do artist have a final say about how their product is produced. Producers have an âintentâ, audio engineers have their own âintentâ, mastering engineers also have their own âintentâ. So by the end of the final product many artist donât have a say in the finished product. But alas, itâs just musicâŠletâs enjoy they way we reproduce music if thatâs in your car, headphones, 2-channel stereo or home theater. Thereâs no right or wrongâŠitâs amazing!
Great video. Wish I understood this when I was first buying speakers as I surely wouldn't own my Jamo S803s that I bought.
I think I could watch videos on frequency response all day. So damn interesting. If you do see a flat instead of a dropping response you talked about near the end, do you need to maybe pump more low end to the speaker, maybe lower hz passover?
A lot of people like a bump in the bass and a roll-off in the high frequencies. What's interesting is this the typical response you would get with a good speaker in a typical room.
You might not want to just set this as the target response because it really depends on what's happening on speaker level also. The sound at your listening position is a combination of direct and reflected sound. With bad speakers, they will have a very dissimilar off-axis response meaning that fixing one will make the other worse.
To me, fixing the nearfield on-axis response while being conscious of the off-axis response is the way I think it should be done. At your listening position, that will likely sound good also.
Bro same!!! It is very interesting. I wish other of my peers shared the same interestđ
I run a modulation effects unit with my guitar and 2 4x12 flat response speaker cabs. They work great for getting the exact sound im after from the modulated sound effects unit.
Man, this is so helpful. Itâs been an awkward road to working this out, will check out the book you mentioned as well. Wanted to ask, of those on your leaderboard, which ones would you say meet that flatter/more balanced response?
Typically the better measuring speakers I prefer to worse measuring speakers. The Larsens I liked but because of the way they were designed to interact with the room. Their frequency response is a bit odd, but they take well to DSP correction. The other bias that I have is I really like speakers that can produce good bass so I have a preference towards those on my leaderboard.
Good chat m8.
Flat frequency response originally meant to me that every frequency would be realistic and equally as likely to be heard. Or to say, it gave every frequency the chance of being heard as every other frequency. In actuality, it hasn't produced desirable results for me.
Now, I don't think flat is "correct": it's not that simple. I think a flat frequency response means certain frequencies will be boosted and others cut to maintain a *flat frequency response*.
So my old idea of giving each frequency equal chance to be played at a certainly decibel level I think there's much more to the audio spectrum than that. The frequency spectrum must not be on a flat or at least our ears don't hear it that way. Just remember with a flat response you're only raising some frequencies and lowering others. While you may perceive "hearing more" that doesn't mean you're hearing it naturally or realistically. Also, in real life you may not hear everything, sounds can be drowned out by other sounds.
I'm kind of eyeballing the harman curve, they aren't the most popular brand for no reason.
I think you're confusing on flat on-axis response of a speaker in an anechoic measurement (what I'm saying should be flat) and a flat target curve with the target being flat in your listening position. I said numerous times in the video that I do NOT recommend that.
The Harman target curve for rooms, not headphones, is a downward slope, with bass boost and a high frequency roll-off. Guess how a speaker that measures flat on-axis anechoically will behave in a room? Probably a lot that Harman target you're talking about. You can also check out the NAD target curve made by Paul Barton. Same school of thought.
Agreed we must consider that some people are more sensitive to certain frequencies than others
I look at it like a stack:
- Accurate speaker frequency response
- Adjustments in bass based on room interactions
- Adjustments based on listener's hearing capabilities
- Global adjustments based on listener preference
- Basic adjustments made on the fly based on source material (think turning the volume down when ads play)
I bought a pair of Cerwin vega SL 12. ONE SPEAKER NEAR A COUCH , THE OTHER NEAR A WALL and entrance to the kitchen = bass shy , but tight on the left and bass heavy and sloppy on the right. Iso platforms did help though. I might go for iso padding on the outside of the speakers too, due to box resonance. Gonna try port plugs, but may not be the answer here.
I think you hit it Joe. Really I think all speakers should have a flat baseline and then if people have tonal preferences they can achieve that with EQ. Seems silly to invest money in a certain color of sound. Start transparent and then adjust for free later outside of the speaker itself.
đŻ
You can have a lot of flexibility with a DSP processor like MiniDSP via Dirac. Change frequency response, base "punchiness" and soundstage character as you want depending on how you measured and what target curve you set. Then, if you did it right, you have all the flexibility with a 4 button remote control, in case of the MiniDSP SHD, for example.
With any loudspeaker, not just the ones with adjustable crossovers.
Hurts a middle class working person first, price-wise, but it is worth it long term.
Yeah already have the book.
The circle of confusion is complete đ€Ł
In the initial image with the megaphone the line is flat BUT sloping downward. In the last graph in the video there is also a drawn flat desired line but it is more horizontal.
Both are flat but have more or less lean angles.
Any thoughts on how much slope is desired if any?
(Or I am probably mixing together in room at sweet spot measurement that has a slope and near field measurement of a speaker that is more horizontal..)
Yes, you caught the downard slope on the image. đ Yes, let's not confuse the two. The downard tilt is for in-room response in your listening position. The amount of tilt will be dependent on how far you are. The further, the more tilt.
@@joentell Thanks for the explanation. đđ”đ¶â€ïž
Yes that is something I have reacted on when i do my own measurements at sweet spot there is always a slope. I have never grasped why.. đ
I use 2 headrush 2000watt frfr speakers with my Fractal axe fx3 ,they actually recommend if you want the true sound to use frfr speakers with modelers like the Fractal unit.at first I didn't listen to them and ran the four cable method through my peavey 60 watt tube head In to a 4x12 Marshall cabinet and it sounded like crap.frfr the way to go when using a modeler
THANKS SO MUCH wow!!.........
Which is why these middle-aged ears love pro mid-field monitors like Genelec, ATC, etc. and intensely dislike traditional "hi-fi" speakers with their designer intended dips and suckouts.
Yeah, the well behaved off-axis is important.
Having only a flat on-axis and saying thatâs all
you need is where people get confused and hear flat on-axis speakers with poor off-axis and get confused and think they heard a neutral speaker that sounded poor, thus thinking actual neutral speakers sound poor.
You're always coming with the proper info! đ
Tone controls don't work well because they don't always affect the frequencies you want adjusted. You may hear too much high end treble but can tell there's a lack in the upper mid-range/low treble. Tone controls won't touch it. You may have chesty bass but not enough low bass, tone control will only help and hurt rather than just help. There's a lot of other scenarios but those are probably the most popular I've dealt with and realized tone controls are nearly useless- they often hurt as much as help.
You are very lucky person if tone controls do you a whole lot of good.
If you have a good speaker that has a good in-room response, tone controls will do what they should. I think what you might be looking for to do specific tuning is parametric EQ. Dsp is usually recommended for that. I actually think you need a calibrated mic if you want to do it properly.
Do you get into measurments?
@@joentell yes I use audyssey and ypao. I own elac ub5, klipsch rp280f, jbl studio 580 and infinity beta 50 (my 1st set of speakers).
I try to understand why so many audiophile reviewers buy high end 2 channel integrated amplifiers that have no room correction and generally only tone controls?
I've wondered if speakers typically work better leaving them as they come factory (without equalization) because that seems to be how audio file reviewers review them (without any equalization aka using speakers with high priced integrated amps that have no room correction)?
For example, The purpose of my curiosity besides simply being inquisitive is I look at the Yamaha such as the as2200 but it seems like a downgrade from my Yamaha aventage 880 which has 7 channels and ypao. Why pay more for seemingly less? (Yes, I understand the amplifier is probably built with better parts but it lacks in technology and the ability to do surround sound.). What's the real payoff? Is music so much better sounding over a high priced 2 channel integrated like Yamaha as2200 over a techy receiver?
Sometimes I wonder if some folks are just anti-technology.
In my experience getting the room response flat before using EQ is the only way to go.
Hi Joe.. I'm Mike frm the Philippines.. Need some help or Advice from u . I plan to buy some speakers.. Which is better the B.i.c America dv64 tower or pioneer FS 52? have pioneer fs52 b4 but I had to sell it due to financial needs.. Tnx in advance God bless
What's up Mike from PI! Sorry, I haven't tried the BIC
The longer you're in home theater or music audio, the more apparent it becomes that flat is best, especially in the lower frequencies.
do flat speakers sound flat? like Magnaplaners ? electrostats ? ect
While I like flat speakers I also do enjoy speakers that have their own sound
Ad far as I know, the only way to get a perfectly balanced speaker is if one either spends a lot of money or uses DSP correction. I've noticed, to my ears anyway, that speakers that are DSP corrected sound kind clinical or lifeless, that are forced to sound like they are alive.
@@arena_rock_man9030 personally I find DSP only works well for bass
Whatever you have +/- off a flat response is *distortion* !
Most speakers are pretty flat response +/- 3db. Rooms however are often +/- 30db (60db peak to peak) off flat. Most people worry about tiny amounts of distortion (not flat response) from their gear when in reality the room adds 50% 60% or even 70% distortion!
After around ÂŁ5k in treatment my room measurements are +/- 8db (16db peak to peak) a studio would be +/- 4db and would require the entire room treating.
Iâm willing to bet 99% of your audience has no, or very little room treatment. But all of them will swop out a pair of perfectly good speakers chasing better sound (less distortion).
The human brain is amazing in it's ability to hear through the room after getting acclimated. Afterwards, all they hear is the speakers. Up to a certain extent of course. Too much early reflection energy will screw up out perception. They've done a lot of research on this and the tests are discussed in more detail in the book I linked to. Interesting stuff.
The problem is not the speakers itâs the environment. A flat speaker wonât sound flat unless itâs in a treated room. What percentage of people have that?
what about room modes? sound insulation? Speaker tonality?
The first two are definitely factors in determining the sound at your listening position. Still a well behaved, neutral speaker has a better chance of sounding good in your listening position.
Speaker tonality is pretty much the same as frequency response.
This concept is most confusing to me. I have a yamaha 2080 receiver that has an adjustable PEQ Parametric setting where you can go in after room calibration and change the speaker graph. Im most likely doin it wrong since I tried moving the graph line for each speaker to a flat response across all frequencies and results were horrible. Maybe its time to try another brand of receiver with audessey or Dirac live.
Audyssey by default lowers bass (makes it flat in-room), so if you go with Audyssey you need the $20 app to adjust it.
How steep should that downward curve really be inroom though? How many db from bass to highs, and where is the -neutral- zero point usually set?
Toole & Olive found an average in-room tilt for highly rated speakers. However, they also noted that based on how wide the dispersion of the speaker is, that really influences the desired tilt.
Basically, donât adjust tilt unless you feel the need to; what you should do though is EQ any bumps/dips in the response.
@@homeboi808
I used Audyssey XT32 and have a decently treated room, so Peaks and Dips do exist, but are manageable.
I have currently created my own custom curve via the Audyssey app, but am always curious to heat what other consider to be "good".
At the moment I use the Audyssey Reference curve as basis and create a steeo slope from 200-100 and then a more shallow slope from 100 to the Crossover that is 60Hz on my Mains and Center.
@@rolandrohde I would look at what Audyssey says the âBeforeâ is, and follow that slope for say 1000Hz and above.
My main issue with Audyssey is it rolls off the highs too much for my taste.
@@joentell
I actually like the HF rolloff...but with the app even that is easy to configure.
Right?
Hey Joe! I made a center channel speaker shootout in honor of the cheap audio man!
I talk about this exact thing at one point when trying to describe how amazing the elac reference center channel was compared to other, also great center channel speakers.
Check it out sometime, I guarantee it will put a smile on your face! đ
Just because something makes sense doesn't mean people are going to agree with it. đ€Łđ đ. I happen to be on Team Flat...when it comes to speakers that isđ€Łđđ
Well I've known plenty of people who hear something that makes sense to them and still be totally wrong too...đ
Bose Acoustimass AM5's are some of the best selling speakers of all time. That says it all.
Just found this channel today! Love the content man. Joe are you Asian? Iâm Asian and my name is also Joe. If thatâs the case thatâs a win for the Joeâs!
Filipino
@@joentell Hell yeah man. Iâm Korean. Iâm from a small town in New England where I am the Asian population and Iâve always found it annoying and comical when people will say to me âOh youâre Korean? Do you know (insert name) heâs my cousins roommate heâs Korean tooâ Iâve gotten that so much in my life my response now is âNo, but Iâll be sure to check him out at our next conventionâ
Audiofools dislike this video!
Denon flat vs Reference for music ?
Neither. Custom curve made for your speakers and your room.
Itâs funny you say that, reise the bass and tilt the trebleâŠ
Thatâs exactly what the Harman curve is for highend monitorsâŠ!
Yep it excist, but not many knows what it is and Think itâs a fail on frequency response curveâŠbut NoâŠ!!
Take a closer look at GR-research youtube ChannelâŠ
He got some ATC monitors he Think theres wrong with the frequency response, but noâŠ
Thatâs the harman curve for monitorsâŠ
If you put a "perfectly accurate speaker" in a room and move back to a normal listening distance, you expect to get an in-room response similar to the Harman curve.
@@joentell you Got it, but a true Harman target curve youâll find it on axis...
But yes a flat response got it 45deg. Off axis.
@@joentell where do you find harman curve...?
Well, jbl is incorporated with harman and youâll therefore find the harman curve on every jbl monitors.
And also on every atc monitors...
I think your brains neuroplasticity will wire to the actual sound eventually and fix the flaws.
Hmmm....maybe after a while that may be partially true. We do get used to sound the same way our eyes adapt to dark/light and white balance. There is a limit to that. You can only turn your screen more blue to a certain degree before your visual abilities will stop compensating. After that, your brain just say, "that screen has too much blue!"
You want a flat frequency response so your speakers best represent the source. Been saying this for years. My buddy cranks the bass and sub volume. Why are my ears bleeding hearing 2 people talk!
Yessir
DnB & Dubstep with a flat EQ curve... Thanks but no ! đ€Ł(i like all genres)
If speaker FR is not flat, it is not HiFi, High Fidelity, period.
Instead of calling it flat output it should be called original output
Flat nearfield maybe. Idk
Are you a marketing/advertising/sales guy? You're absolutely right. From now on, we're going to look at frequency response as percentage on the "accuracy scale." The closer a speaker is to 100%, the closer it is to Perfect Accuracy. Any deviations will be called out as such (I.e. boosted +3dB from 300-400hz, dip -3dB at 3khz.) đ€Ł I'm joking of course, but it almost makes more sense to say it in that manner. The traditional way of looking at frequency response almost makes it look like an accurate response is optional instead of ideal.
Anybody interested in how music is recorded ? A great channel "produce like a pro" with warren haurt.
some genre/tracks are mastered for radio or other crap source.. or for the car audio system..
the question is do you want these tracks/genre to sound good or do you want all rightly mixed/mastered for perfect system genre/tracks.. .
this is why its stupid to review speaker with rock or shitty mixed, mastered crap..
i dont like reviewers who listen to cheap crap music and prefer not neutral chain & speakers to make their crappy music sound good..
Yes a flat frequency response matters but everyone in the world never had a flat frequency before cuz the chances of you getting a flat frequency response is equal to the chances of an average person getting a hole in one on a golf course
Seems to be a lot of focus on this topic here recently by a few select CZcamsrs and reviewers. At this point it seems pretty much beaten to death (over the past month or so) and I think most folks will look at frequency charts, but that won't necessarily be the deciding factor. And unless one has a lot of cash to spend, most speakers in an "average guy" salary range are a compromise in one way or another, so they have to pick their poison, so to speak.
Its kind of like car shopping...specs and measurements are one thing, but you may hate it once you finally drive it. And what may be a "flaw" to some may be a positive to another.
What scares me about this reviewer push for "flat" speakers is that we will see a lot of flatter speakers at the expense of bass extension. With today's tiny boxes and small woofers, that's the last thing some of us want.
Regarding your last comment about bass extension, flat frequency response has no bearing on bass extension. Bass extension, the size of the enclosure, and sensitivity are interrelated according to Hoffman's Iron Law, but not how flat a speaker is.
I think it's an interesting time because we now have the data available to us that wasn't always available or consistent. Right now is the time people are interested in knowing what makes a flat frequency response good? How do I interpret the data on a graph?
Regarding your car analogy, I'm into sports cars. Of course horsepower, torque, power/weight ratio, 0-60 and 1/4-mile times, top speed all play a factor in someone's purchasing decision. Sure, it's fun to watch a video of someone driving a car explaining what the experience is like. That's the subjective part. And of course, you should test drive the car. But that doesn't make the specs less relevant in any way. This video is like talking to someone about how horsepower and torque are related and how that might translate to driving experience. And sure there are always compromises to be made one way or the other, which makes understanding specs even more important.
Yes, the experience is what matters in the end. But a truly great experience whether it's cars or audio, is because of great engineering and not just a happy accident. When a product is great, you don't have to think of the how, you just enjoy the experience. But someone had to take the time to figure out the how. That's what we're getting to. What makes a great system sound great?
It's just about sharing knowledge, not about creating drama.
Flat does not sound good. Mixing relative to flat will make it sound good.
I can get with that statement. The issues is people think flat = boring, where it really just means neutral or accurate.
This is all moot after age 45.......
Flat response only makes sense in home theatres, for dsp processing...
High end stereospeakers takes care of the problem with the human hearing, and sound terrific but for stereo...
Sorry, I don't understand what you mean that high-end stereo speakers take care of the problem with the human hearing. Those speakers also have to follow the laws of acoustics.
Flat sounds rather.....flat.
Yes, if the sound going in is flat. If the sound going in is dynamic, then the sound coming out will be equally dynamic.
Off axis response is important because a lot of the sound you hear at the listening position is reflected sound.