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Question about EQing speakers above 500 Hz

With 100 sweeps on same location and speakers you Will have 100 different outcomes above 500 hz.
You cant correct for something you dont know what it must be.

I essentially agree with you, and this is one of the reasons for at least I myself prefer accurate and highly reproducible "cumulated/recorded white-noise FFT averaging" method, not short/rapid sine-tone sweep, in my Fq-SPL measurements.

If you would be interested, please refer to my relevant posts on my project thread and on remote threads:
- Frequency response measurements by "cumulative white noise averaging": #392, #404 (including summary of pros of the method), especially the end portion of #297(remote thread) by Dr. Floyd Toole, #315(remote thread) by Dr. Floyd Toole, #125(remote thread with typical example diagrams)
 
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With 100 sweeps on same location and speakers you Will have 100 different outcomes above 500 hz.
You cant correct for something you dont know what it must be.
This seems absurd. Are your walls and furniture constantly shifting? :p

The room remains the same.
The speakers stay the same.
The mic doesn’t change.
The location is fixed.
The sweep is consistent.

So, explain to me again why the measurement should vary each time? - It doesn't.

However, if you take a single-point measurement one day and another on a different day, they will differ -not because anything has changed, but due to user error (the microphone's position.)

Relying on a single-point measurement is never a good idea. Use MMM in REW or Dirac Live's multi-point measurements, and you'll be set.
 
Unfortunately, our ears don't work that way. Well, they kind of do work that way below 500 Hz (some say 300 Hz, but let's use 500 for now), but they definitely don't work that way above 500 Hz.

So why do my ears tell me it sounds better when I use Dirac to correct my speakers up to 20 kHz? Why does almost all room correction software allow for correction above ~500 Hz if 'it definitely doesn't work'? These are not subtle effects. The improvement in imaging and spatial clarity is unmistakeably real at mid to high frequencies.

It may be that anechoic correction coupled with 'proper' (physical) room treatment is theoretically better at higher frequencies but the proof, as the saying goes, is in the pudding. Sometimes good enough is good enough ...
 
This seems absurd. Are your walls and furniture constantly shifting? :p

If he (@Palmspar) would use very rapid and narrow-Fq-window sine-sweep on not-so-sophisticated measurement software, the FFT results could be fluctuated due to statistic error (or I can say due to "lack of enough raw data") giving non-reproducible Fq-SPL spectrum in each of the 100-time measurements.

Some of the too-much smoothing (such as psycho-acoustic smoothing) would have tendency of hiding/flattening all of such statistic-error-oriented fine structure of Fq-SPL spectrum., and hence sometimes give non-reproducible results.

We need rich-enough raw acoustic data for reproducible FFT results, and of course we always need to properly know/understand what mathematical/statistical theory the FFT spectrum analysis is depending on.

These points are also part of the many reasons for my personal preferences on Fq-SPL spectrum analysis using "cumulative/recorded (rich data) white-noise FFT averaging", as I shared in above post #21.
 
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Let's take it from the source once again,I quote some of it:



"
OK. I thought about opening a rat's nest by doing this, because it is a simplification of what sometimes has to be done. Some of the points have been made earlier in this forum thread and elsewhere, but it might be useful to bring the key factors in the process to one place. The marketing of room EQ algorithms often presents the impression that all combinations of loudspeakers and rooms can be "fixed", "calibrated" or the like, by means of measurements, math and equalization. In reality, much of the "math" does not include the exceptionally complex, non-linear and occasionally capricious psychoacoustics of human listeners. A critical missing element is that humans adapt to circumstances, bringing our perceptions into acceptable territory. Loudspeakers reproduce sounds. Musicians produce sounds. Both do it in rooms. We don't feel the need to "equalize" - even if we could - the instruments and voices of live music. Two ears and a brain separate the sources from the venue, and adapt to aspects of what the environment contributes to the overall performance. The venues vary, and some are even not ideal, but we manage to appreciate the excellence of fine instruments and voices in most of them.

The special problem with sound reproducing systems is that flaws get superimposed on everything that is played through them. These monotonous colorations can sometimes be beyond the ability of humans to adapt, and they need to be identified and attenuated.

Therefore, the "right way" begins with choosing well designed, timbrally neutral, loudspeakers. If the loudspeakers exhibit audible resonances and/or frequency-dependent directivity issues, it is not likely that measurements in a room will reveal such problems and that equalization is capable of compensating for them. It is often the case that the solution is better loudspeakers. Fortunately these can be identified with good reliability from competently made anechoic measurements presented in a "spinorama" format, following the industry standard. Amir, on this site, makes such measurements and others can be found at www.spinorama.org.

This done, set them up in your room and make a steady-state frequency response measurement at the prime listening position - the stereo seat. We will be paying close attention to the frequencies below about 400-500 Hz, where adjacent boundary effects and room resonances are active. Because much of the bass in recordings is mono (all of it in LPs) drive both loudspeakers simultaneously to evaluate what is happening at low frequencies. Measure them individually to find out what is happening at frequencies above about 400 Hz. If you are using bass management and one or more subwoofers the process is the same, and of course all subs should be running simultaneously. Why? Because multiple sound sources couple energy to room resonances differently when they operate in unison."

...the rest here:



 
So why do my ears tell me it sounds better when I use Dirac to correct my speakers up to 20 kHz? Why does almost all room correction software allow for correction above ~500 Hz if 'it definitely doesn't work'? These are not subtle effects. The improvement in imaging and spatial clarity is unmistakeably real at mid to high frequencies.

It may be that anechoic correction coupled with 'proper' (physical) room treatment is theoretically better at higher frequencies but the proof, as the saying goes, is in the pudding. Sometimes good enough is good enough ...
I think it's more about your specific speakers/room than whether you just need to worry about schroeder. Then again your preference is what it is....
 
I’d like to remind everyone that what we’re discussing here is simply EQ.

Just as people have individual preferences for adjusting the treble and bass knobs based on their taste, everyone’s preferred correction curve will naturally have its own unique shape. Additionally, the bass and treble knobs aren't aware that they "should or should not be used above 500 Hz." However, adjusting them would likely still yield significantly better results than not making any adjustments at all. This is what room correction is. And some trial and error is needed to get the result right.

Not more to it, in my opinion. :)
 
So why do my ears tell me it sounds better when I use Dirac to correct my speakers up to 20 kHz? Why does almost all room correction software allow for correction above ~500 Hz if 'it definitely doesn't work'? These are not subtle effects. The improvement in imaging and spatial clarity is unmistakeably real at mid to high frequencies.

It may be that anechoic correction coupled with 'proper' (physical) room treatment is theoretically better at higher frequencies but the proof, as the saying goes, is in the pudding. Sometimes good enough is good enough ...
Why does fast food exist. Why do small bluetooth speakers exist. Why did Bluray succeed over HD-DVD. And so on - you can ask the question for every matter but that's not the proove that something is objective good, right? Otherwise there wouldn't be so much bad products on the market.

To my experience, in acoustically horrible rooms full range correction may sound a little less bad than without. It simply doesn't matter when something is lost because you don't recognize it anyway - that may be a reason. Also in home cinema systems, it may have an positive impact (according to my experience) because something like "imaging" is done by physical speakers. But as soon as you listen to stereo music in an acoustically not so bad place, you will notice how much of the sound get destroyed by that - especially with Dirac. There are other systems doing better in that but unfortunately the mass consumer market adopts dirac.

So from my point of view, I could ask the same question like you: why does it exist. But for other reason.
 
…. We all come to ASR for Amir's reviews and everyone here pretty much loves Erin's reviews.
:rolleyes: (Subtle)

I often see them reference applying correction to a speaker above 500 Hz to rectify a given problem.
To fix a room problem?
or
To fix a speaker problem?

So, those corrections are above 500 Hz. That is the heart of my question. Do Amir and Erin believe in applying correction above 500 Hz? Or do they only believe in correcting the "anechoic measurement"? …
You may want to ask them (Amir and Erin),
(I am not sure I can read either of their minds well, but I think I can read Erin’s mind better than Amir’s.)
However… I have seen Erin use Klippel measurement which shows/says “anechoic” like measurements that have FR issues, so that is not “room issues”.

What is most important to you?
  • If it is the frequency response, then just get a speaker with a better FR.
  • If it is directivity first, then fixing up FR could be a thing.
  • And it could yet something else entirely.
 
Why does fast food exist. Why do small bluetooth speakers exist. Why did Bluray succeed over HD-DVD. And so on - you can ask the question for every matter but that's not the proove that something is objective good, right? Otherwise there wouldn't be so much bad products on the market.

To my experience, in acoustically horrible rooms full range correction may sound a little less bad than without. It simply doesn't matter when something is lost because you don't recognize it anyway - that may be a reason. Also in home cinema systems, it may have an positive impact (according to my experience) because something like "imaging" is done by physical speakers. But as soon as you listen to stereo music in an acoustically not so bad place, you will notice how much of the sound get destroyed by that - especially with Dirac. There are other systems doing better in that but unfortunately the mass consumer market adopts dirac.

So from my point of view, I could ask the same question like you: why does it exist. But for other reason.
DIRAC does phase EQ as well as FR-EQ.

I doubt that the @bluefuzz would have found DIRAC to have a big difference on a time-and-phase correct speaker… as it is already time and phase correct.
 
DIRAC does phase EQ as well as FR-EQ.

I doubt that the @bluefuzz would have found DIRAC to have a big difference on a time-and-phase correct speaker… as it is already time and phase correct.
I know what Dirac does - what lead you to the assumption I won't?
 
But I am far from alone in this perception. It's quite plainly not about my specific speakers.



Ah! So I just have cloth ears? That explains everything ...
Don't become insecure and get unnecessarily hostile, it's always an interesting discussion. Both opinions are perfectly valid. Your opinion is perfectly valid

It could be about somebody's speakers in the sense they have large dips and peaks on axis in anechoic measurements. That may well correspond to your room measurements, so that full range correction sounds better to you as it is objectively better.

Same with the room, low ceiling equals more harmful reflections - speakers close to the side walls also - listening position up against the back wall very harmful imo, certainly in my case.

It can be your speakers and/or your room making full range correction sound better. If it isn't, then why does it sound better?
 
that's not the proove that something is objective good, right?

Nor is it proof that it is objectively bad.

in acoustically horrible rooms full range correction may sound a little less bad than without.

My room is by no means acoustically perfect but it is certainly not horrible. It is a typical smallish living room with quite a lot of 'stuff' in it and so fairly well damped. Loudspeakers sound fine on the whole but inevitably suffer somewhat from asymetric placement too close to walls and furniture etc. to the detriment of perfect imaging and soundstage. And this is precisely what Dirac is able to improve.

It simply doesn't matter when something is lost because you don't recognize it anyway - that may be a reason.

Ah! Again, I'm simply too dumb to be able to tell the difference between good and bad sound? Fair enough ... ;-)

Also in home cinema systems, it may have an positive impact (according to my experience) because something like "imaging" is done by physical speakers. But as soon as you listen to stereo music in an acoustically not so bad place, you will notice how much of the sound get destroyed by that - especially with Dirac.

I'm not talking about home cinema here. I'm talking about pretty good sounding stereo (2.1) speakers in a pretty good sounding room. There's certainly nothing getting 'destroyed'. Your argument sounds like a case of the perfect being the enemy of the good. No one is claiming that Dirac (or similar) is the be all and end all of room correction, but for a wide range of typical consumer loudspeakers in typical listening conditions it works very well ...
 
Don't become insecure and get unnecessarily hostile

I'm neither hostile nor insecure. But perhaps a little nonplussed by people seeming to claim that I (and many others) are not hearing what we say we're hearing and even claiming it is 'impossible'. These are not imaginary differences between two SOTA dacs or comparisons between audiophile speaker cables ...

It can be your speakers and/or your room making full range correction sound better.

Well exactly. That's the whole point!
 
Interesting outcome (or not :facepalm: ) if you leave out 8% other it is close to 60% Schröder an 40% full range.
From a pure technical point of view i acspected something close to 90-10 regarding theory specific ask in a ASR group.

 
So why do my ears tell me it sounds better when I use Dirac to correct my speakers up to 20 kHz?
Your ears could tell you anything. Your ears could tell you that $5000 interconnects transform the sound of your system to another plane. So what?

Why does almost all room correction software allow for correction above ~500 Hz if 'it definitely doesn't work'?
Marketing. The idea of it working well is compelling. Did you actually read with care the paper I linked in my post that you are replying to? If you did, you would not be so confident that your above question is a reason that 'room correction of summed sound' is a good idea above 500 Hz.

The paper does not claim that summed-sound EQ above 500 Hz will invariably make speakers sound worse. You would already know this if you had given it a good read, and wouldn't be misrepresenting it as you are. Rather, the paper demonstrates that such EQ turns the result into a lottery: the change could be for the better, for the worse, or null, but the whole approach simply doesn't generate the correct data to control which outcome occurs. So that makes it a really bad idea. And especially so when, in the case where the speakers themselves have outstanding direct-sound frequency response and excellent directivity control, then pretty much any EQ adjustment above 500 Hz is going to be detrimental. But if your speakers have pretty bad problems in their direct-sound frequency response, then the chances that the 'lottery EQ' will actually improve the direct sound improves...somewhat.

These are not subtle effects. The improvement in imaging and spatial clarity is unmistakeably real at mid to high frequencies.
Effects being 'not subtle' is not evidence that they cannot be the result of perceptual filters or bias effects, which can (and routinely do) create strongly 'not subtle' effects.

It may be that anechoic correction coupled with 'proper' (physical) room treatment is theoretically better at higher frequencies but the proof, as the saying goes, is in the pudding. Sometimes good enough is good enough ...
Sighted listening is not a pudding that proves anything about what is in the sound waves. There is no 'proof' in that 'pudding'.

PS - stop posting that people are telling you that you have cloth ears or are too dumb to tell good from bad sound. You seem to be revealing that you are not aware of psychoacoustic phenomena like the sighted listening effect, cognitive bias, placebo effects.... these are practical realities for all audiophiles to come to terms with. The whole idea that you, I, anyone here, is immune to these effects and can magically discern the sonic attributes without having to implement any experimental listening controls, is just not realistic. Yet such immunity is exactly what you are claiming to have when you assume that you are being insulted. Nobody is insulting you: they, we, are just mentioning the indisputable fact that we all mistakenly and naturally think we are much more immune to these effects than we really are.
 
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Nor is it proof that it is objectively bad.
You used this argument to make your statement, not me.
Ah! Again, I'm simply too dumb to be able to tell the difference between good and bad sound? Fair enough ... ;-)

And I also didn't say that. It's hard to discuss something neutral when you take statements personal and behave defensive.
 
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