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Some comments from Floyd Toole about room curve targets, room EQ and more

dasdoing

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Didn't read all, but our ultimate goal should be finding the correct form of windowing our room meassurement to the sound our ears are percieving. it is clear that a form of frequencie dependent windowing is necessary. once this windwing method is found the target is a perfect flat.
may I sugest some papers Bob Katz is sugesting in this post for the next book? https://www.hometheatershack.com/th...dependent-windowing.99673/page-3#post-1224050
 

krabapple

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Didn't read all, but our ultimate goal should be finding the correct form of windowing our room meassurement to the sound our ears are percieving. it is clear that a form of frequencie dependent windowing is necessary. once this windwing method is found the target is a perfect flat.
may I sugest some papers Bob Katz is sugesting in this post for the next book? https://www.hometheatershack.com/th...dependent-windowing.99673/page-3#post-1224050

Since that link in Bob Katz''s post doesn't work any more, here are links to the abstracts of the three preprints he was referring to (#7263, 8314, and 8379):

A Low Complexity Perceptually Tuned Room Correction System

Beyond Coding: Reproduction of Direct and Diffuse Sound in Multiple Environments

DTS Multichannel Audio Playback System: Characterization and Correction


JJ (James Johnston) is an author on all of them

Given their age I would be surprised if Dr. Toole hadn't encountered them already.
 

nathan

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Undoubtably he was aware of them since they predate some of his more recent papers. That said, the few I have access to don't seem to cite these papers and I don't see them mentioned in his book. If he thought they were pertinent (to that subset of his papers I have access to) I'd have expected them to be mentioned. Note I'm not suggesting he disagrees with their conclusions.
 

dasdoing

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Undoubtably he was aware of them since they predate some of his more recent papers. That said, the few I have access to don't seem to cite these papers and I don't see them mentioned in his book. If he thought they were pertinent (to that subset of his papers I have access to) I'd have expected them to be mentioned. Note I'm not suggesting he disagrees with their conclusions.

I think this stuff is a new door one needs to enter. does he even recognize that two FR curves that meassure equal in a 500ms window will sound diferent in 2 different rooms/distances?

there also is another intresting concept used by the Kipple near field scanner. it seperates direct and room sound by observing where the soundwaves com from which they call "acoustical holography". he explains a little bit of this in this video

I wonder if we could do something like that in REW by comparing 2 meassurements with diferent distance
 

dasdoing

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Since that link in Bob Katz''s post doesn't work any more, here are links to the abstracts of the three preprints he was referring to (#7263, 8314, and 8379):

A Low Complexity Perceptually Tuned Room Correction System

Beyond Coding: Reproduction of Direct and Diffuse Sound in Multiple Environments

DTS Multichannel Audio Playback System: Characterization and Correction


JJ (James Johnston) is an author on all of them

Given their age I would be surprised if Dr. Toole hadn't encountered them already.

now, I found a sweet power point from him: http://www.aes-media.org/sections/pnw/pnwrecaps/2008/jj_jan08/
 

Mike Lima

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My actual measurements don't look much different in terms of the resulting EQ'd curves in terms of accuracy to the curve, but I've chosen now to use a "Full" Harman Curve for all Movies/TV/Music. I'm hoping that Amir will measure the JBL 308p Mkii (which is the same speaker I have), it's in his pipeline to do he's said......at which point I'll have a go at using his spinorama measurements to EQ the mids & treble (above the room modes). At the moment I'm happy with the my EQ'd results so far, so I'm not gonna do anymore tweaking until I get to see a spinorama. I have a feeling the JBL 308p Mkii might not measure that well, so that might be a little niggle in the back of Amir's mind that he could do without the slightly tricky waters of reviewing a not so well performing Harman product......I mean I'm pretty sure it's fixable with EQ in my experience, but yeah.

Can you please share with me what your Full Harman Curve for movies looks like? Do you have it in a text file? This is what I am using.
How does yours look like?

24 10.5
31.5 10.5
32.8 10.5
36.2 10.5
39.08 10.5
40 10.5
50 9.425
63 7.5
80 5.325
100 4.575
125 3.325
160 2.6
200 2.5
250 2.025
315 1.75
400 1.675
500 1.675
630 1.325
800 1.67
1000 1.35
1250 1.25
1600 1.375
2000 1.525
2500 1.2
3150 1.2
4000 0.875
5000 0.125
6300 0
8000 -0.125
10000 -1.25
12500 -1.5
16000 -1.875
20000 -4.785
 

Robbo99999

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Can you please share with me what your Full Harman Curve for movies looks like? Do you have it in a text file? This is what I am using.
How does yours look like?

24 10.5
31.5 10.5
32.8 10.5
36.2 10.5
39.08 10.5
40 10.5
50 9.425
63 7.5
80 5.325
100 4.575
125 3.325
160 2.6
200 2.5
250 2.025
315 1.75
400 1.675
500 1.675
630 1.325
800 1.67
1000 1.35
1250 1.25
1600 1.375
2000 1.525
2500 1.2
3150 1.2
4000 0.875
5000 0.125
6300 0
8000 -0.125
10000 -1.25
12500 -1.5
16000 -1.875
20000 -4.785
This is the one I use:
31 5.6
40 5.9
50 5.5
63 4.9
80 3.7
100 2.5
125 1.3
160 0.6
200 0.2
250 0
1000 -1
32000 -6

I don't use the Harman Curve anymore for music nor for movies, instead I use an Anechoic EQ of my JBL 308p Mkii speakers from Amir's measurement on this website........however it does happen to closely track the Harman Curve when I measure my speakers in my room at my listening position.

I notice there's some differences between what I was using and what you listed. Comparing the difference between 200Hz and 31Hz I have 5.4dB difference and you have 8.5dB difference. Judging by looking at the graph here from the research, then it looks like mine is more accurate at that point, haven't compared your other points, mine is following the All Listeners solid line:
Harman Curve.jpg

My Harman Curve is in the attachment at end of post.
 

Attachments

  • Harman Curve.txt
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Mike Lima

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Interesting. Thank you for your quick response. I can see it was done using a specific speaker. I was wondering how I would create one off this.
1620332502581.png
 

JoachimStrobel

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This is the one I use:
31 5.6
40 5.9
50 5.5
63 4.9
80 3.7
100 2.5
125 1.3
160 0.6
200 0.2
250 0
1000 -1
32000 -6

I don't use the Harman Curve anymore for music nor for movies, instead I use an Anechoic EQ of my JBL 308p Mkii speakers from Amir's measurement on this website........however it does happen to closely track the Harman Curve when I measure my speakers in my room at my listening position.

I notice there's some differences between what I was using and what you listed. Comparing the difference between 200Hz and 31Hz I have 5.4dB difference and you have 8.5dB difference. Judging by looking at the graph here from the research, then it looks like mine is more accurate at that point, haven't compared your other points, mine is following the All Listeners solid line:
View attachment 128248
My Harman Curve is in the attachment at end of post.
I have commented that room curve in another thread in a quite impolite way and try again here:
Why is it that untrained listeners want 10 dB more treble and bass? Can people that know the details comment on these untrained listeners? Otherwise, is it not bizarre to exclude those listener‘s taste in discussions about room curves? Is this like a burger tasting for Michelin-Guide affine people and all others, where only Michelin grade tasters like little salt, pepper and grease while others like more? I am still puzzled about the message that this graph sends and am amused that its message is not discussed here. I confess that I like the „untrained“ curve and use it. Sounds great, may be a bit too much bass at high levels, otherwise, as said, it sounds great. Btw, I chose my restaurants mostly with a Michelin guide...
 

Geert

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Why is it that untrained listeners want 10 dB more treble and bass?
Because the result is fun and spectacular. It takes some experience to learn it's just sugarcoating.
Although you also need to take the equal loudness curves into account (Fletcher Munson). Which means that at lower levels you can use a bit of a low and high end boost (loadness control).
 

tuga

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Perhaps it makes sense from a commercial point of view to design entry-level speakers with a "tailored" response after all.
 

JoachimStrobel

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Because the result is fun and spectacular. It takes some experience to learn it's just sugarcoating.
Although you also need to take the equal loudness curves into account (Fletcher Munson). Which means that at lower levels you can use a bit of a low and high end boost (loadness control).
.... sugarcoating. The same can be said about Sweet dessert. And yes, the low frequency part of the untrained people‘s preferred curve is almost identical to the FletcherHenderson curve at 70-80 dB.
Again, the said Diagramm is a testimony that we do have a two-tier audio market. And the Forum members do belong to the upper tier. And the equipment producers - should they label their products according to the target group?
 

tuga

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Frgirard

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Most definitely!



I disagree. It's after all a matter of taste. People are obsessing too much with this house curve thing and some may end up disappointed.

the house curve with a boost in bass frequency with music with a boost in bass frequency ...
the house curve with a boost in bass frequency with music as the piano cut at 2kHz ...

The hourse curve is a crappy concept used to try to solve bad speakers issues and accoustic issues.
 

Geert

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The hourse curve is a crappy concept used to try to solve bad speakers issues and accoustic issues.
It depends on what you do with the curves, and that's fully up to you.
 

tuga

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The Toole/Harman Housecurves are actually statistics on average taste...
It depends on what you do with the curves, and that's fully up to you.

Like I said, it's a matter of taste. That is why people buy different speakers.
Besides, I find the Harman preference assessment flawed.
 

Robbo99999

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Interesting. Thank you for your quick response. I can see it was done using a specific speaker. I was wondering how I would create one off this. View attachment 128349
Harman Curves would be designed for use with measurements at your listening position. Was that at your listening position? You'd either do a number of single point measurements with your mic at slightly different positions (maybe a 40cm box area) at your main listening position, then you'd do an average of those measurements in REW to try to represent better what you're really hearing. There's also the MMM method for taking measurements at your listening position, so that might be worth a try as an alternative to the single point measurements I describe. You'd then try to lower any excessive peaks in your bass with EQ, and if you know your speaker really has an anechoic frequency response similar to the measurement you've shown (as in that rising treble), then you'd probably want to EQ that down. You can choose any room curve you like if you want to EQ to a room curve, however I've decided to not EQ to a room curve....I'm just using anechoically flat EQ'd speakers (Listening Window EQ) based on Amir's measurements of my speaker, and I've done measurements at my listening position after EQ and it just happens to follow the downward curve of Harman quite accurately, and the bass peaks generally line up with Harman too without any room EQ.
 
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