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Harman curve for loudspeakers

dasdoing

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FWIW, my view is that looking at the in-room response is the wrong way to go in the first place.

yea, this is kind of what I said. the percieved brightness of two HF curves meassureing the same can vary a lot. if it realy can't be meassured (somehow by including time domain/phase), the only way to determine the steepness is by ear, like Bob Katz sugested on Facebook

A speaker should measure anechoically flat with smooth dispersion. How it should measure in a particular room should be how an anechoically flat speaker with smooth dispersion measures in that room.

this can be one way to do it (at least for the HF part). that gives the most natural response of you room. problem is when your room sounds diferent from where it was mixed/mastered. the engenier would have balanced the music diferently in your room

That is really loud (SPL)

to see the real SPL my REW should be calibrated to the level where meassurements where taken. so, this values are meaningless
 

andreasmaaan

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this can be one way to do it (at least for the HF part). that gives the most natural response of you room. problem is when your room sounds diferent from where it was mixed/mastered. the engenier would have balanced the music diferently in your room

Yeh, but the problem is that the direct sound of a speaker (at frequencies of wavelengths that are short compared to the listening room) is the primary determinant of perceived tonal balance.

If you start modifying an anechoically flat speaker’s tonal balance (except at low frequencies) to match an in-room target, you are sacrificing the thing that is more perceptually important to perceived tonal balance (the direct sound) in favour of something that is less perceptually important (the in-room response).
 

Thomas_A

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I’ve been pondering the harman curve this morning, or more specifically why the convention is to measure headphones with references to the harman curve, but to measure loudspeakers with reference to an ideal flat response. Perhaps for professional monitoring a flat loudspeaker response is ideal, but if Harman found that users prefer a non linear frequency response in a headphone, is there any research that suggests a similar preference for non linear frequency response in speakers and if so why is that not the reference for non professional loudspeakers?

You will see differences in timbral effects using a mono speaker vs a mono sound reproduced using stereo speakers. So you will have to make a compromise.
 

dasdoing

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Yeh, but the problem is that the direct sound of a speaker (at frequencies of wavelengths that are short compared to the listening room) is the primary determinant of perceived tonal balance.

If you start modifying an anechoically flat speaker’s tonal balance (except at low frequencies) to match an in-room target, you are sacrificing the thing that is more perceptually important to perceived tonal balance (the direct sound) in favour of something that is less perceptually important (the in-room response).

that's a good point actualy. I allready flirted with the idea to eq speaker only above 1000Hz and now I want to try it out even more
 

andreasmaaan

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that's a good point actualy. I allready flirted with the idea to eq speaker only above 1000Hz and now I want to try it out even more

I was actually suggesting not to EQ the speaker above 1000Hz :)

I would only EQ a speaker to deviate from a flat anechoic response at frequencies where wavelengths are long compared to the room’s dimensions (typically <300ish Hz).

If the goal is neutrality/fidelity, I wouldn’t touch an anechoically flat speaker above 1kHz...
 
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dasdoing

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I was actually suggesting not to EQ the speaker above 1000Hz :)

I would only EQ a speaker to deviate from a flat anechoic response at frequencies where wavelengths are long compared to the room’s dimensions (typically <300ish Hz).

If the goal is neutrality/fidelity, I wouldn’t touch an anechoically flat speaker above 1kHz...

you missuderstood. when I said eq the SPEAKER above 1000Hz, I meant making it anechoically flat.
then combine that with a flat in-room response below 1000Hz.
the resulting in-room whole range meassurement will have the natural tilt of the room
 

andreasmaaan

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you missuderstood. when I said eq the SPEAKER above 1000Hz, I meant making it anechoically flat.
then combine that with a flat in-room response below 1000Hz.
the resulting in-room whole range meassurement will have the natural tilt of the room

Ok, clear :)
 

Tangband

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Yeh, but the problem is that the direct sound of a speaker (at frequencies of wavelengths that are short compared to the listening room) is the primary determinant of perceived tonal balance.

If you start modifying an anechoically flat speaker’s tonal balance (except at low frequencies) to match an in-room target, you are sacrificing the thing that is more perceptually important to perceived tonal balance (the direct sound) in favour of something that is less perceptually important (the in-room response).
+1. This is my conclusion to.
 

dasdoing

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The more I learn the more it becomes clear the only solution is "old fashioned tone controls" ..

it is fact that even if you land in the perfect middle, some music will be too bright and some to dull.
but the best solution is to have 3-ish filters with varying HF tilts above 1000Hz
 

levimax

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it is fact that even if you land in the perfect middle, some music will be too bright and some to dull.
but the best solution is to have 3-ish filters with varying HF tilts above 1000Hz
Why would "3-ish filters" be better than an infinitely adjustable filter that can be "tuned by ear" in real time? I find using DSP software EQ programs to be a terrible substitute for tone controls.
 

dasdoing

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Why would "3-ish filters" be better than an infinitely adjustable filter that can be "tuned by ear" in real time? I find using DSP software EQ programs to be a terrible substitute for tone controls.

well. it depends on what the tone control realy does to the FR. I actualy have no clue. I suspect they are basicly high and low shelfs? a high shelf wouldn't reproduce a natural in room tilt
 

levimax

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well. it depends on what the tone control realy does to the FR. I actualy have no clue. I suspect they are basicly high and low shelfs? a high shelf wouldn't reproduce a natural in room tilt
The way I use tone controls is after I have my base EQ set I use tone controls for fine tuning for some recordings that seem off. I also have a complete bypass. Tone controls usually use a Braxandall circuit https://sound-au.com/dwopa2.htm which works well in most cases to adjust for " the circle of confusion as well as preference".
 

Music1969

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I do tone control while preserving driver time alignment and digital room EQ

With target curves I like in Audiolense, which produces the convolution filters.
 

Putter

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yea, this is kind of what I said. the percieved brightness of two HF curves meassureing the same can vary a lot. if it realy can't be meassured (somehow by including time domain/phase), the only way to determine the steepness is by ear, like Bob Katz sugested on Facebook



this can be one way to do it (at least for the HF part). that gives the most natural response of you room. problem is when your room sounds diferent from where it was mixed/mastered. the engenier would have balanced the music diferently in your room



to see the real SPL my REW should be calibrated to the level where meassurements where taken. so, this values are meaningless

Isn't this Floyd Toole's 'Circle of Confusion' which is that every recording/mastering studio has different speakers and room absorption. This would seem to go back to the measuring flat in an anechoic chamber as at least a reference point and using speakers/tone controls/room absorption as the variables to approximate the original recording?
 

dasdoing

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Isn't this Floyd Toole's 'Circle of Confusion' which is that every recording/mastering studio has different speakers and room absorption. This would seem to go back to the measuring flat in an anechoic chamber as at least a reference point and using speakers/tone controls/room absorption as the variables to approximate the original recording?

I have not studied his work. I wonder if he ever tried to established a method to EQ sound at the LP of any given room to produce x_in = x_out....because there is this problem we discussed above that the meassured frequency response doesn't tell the whole story in the high frequencies since our ears seperate direct sound from (some of the) reflected one.
so the solution to the 'Circle of Confusion' whould be a) to have this method, b) pros using it, c) consumers using it
 

dasdoing

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b) pros using it

that would be the hardest part actualy...after all those years they are still insisting in introducing analog distorsion in the production chain.

So we better a) find the method, b) find out x_out of the producer, c) use the method to aproximate x_out of the producer
 

dasdoing

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I was actually suggesting not to EQ the speaker above 1000Hz :)

I would only EQ a speaker to deviate from a flat anechoic response at frequencies where wavelengths are long compared to the room’s dimensions (typically <300ish Hz).

If the goal is neutrality/fidelity, I wouldn’t touch an anechoically flat speaker above 1kHz...

man, I realized Denis Sbragion's DRC always basicly only corrected direct sound above 1000Hz. I was stupid enough to always interpret the resulting curve as an error, and ajusted the target acordingly.
ever since this topic I searched for the best solution to window out the direct sound above 1000Hz and I am pretty convinced that Denis Sbragion's DRC windowing is more advanced then REW's FWD filtering. for two reasons: 1) https://www.diyaudio.com/forums/ful...-driver-range-line-array-191.html#post4620292 2) when you read his documentation on his software you realize how much thought has been put into every aspect of it.
So I tried out his software for the first time with a flat target.
resulting curves (L and R) are this (ignore the dips around 250Hz...I still will adress that...thses filters are "beta")
var.jpg


i thought: "wtf, if flat is too bright these curves bascily flat but with that boost around 3k will be even worse"

this is 5 cycles FDW in REW (ignore stuff below 1000Hz):

direct.jpg


if you consider the diferences in REW windowing and DRC windowing pointed out in the diyaudio post linked above the direct sound is basicly flat.

so how does it sound? I can't belive what I am hearing, for real. shit is seams totaly balanced. I am amazed

*note that my room has a lot of absorbtion panels....."normal rooms" would result in a totaly diferent 500ms curve and would probably be falling more like the Harman curve
 
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