Room Correction: How, why, where?

[mandrix]

I do agree that it's benefits are worth it's "bugs" but personally do find the changing of the rear balance annoying. I've tried to compensate for it by "re-adjusting" the rear levels but the fact that it is dynamic and changes with volume level makes it impossible to completely correct for.
I have for years hoped that the powers at Audyssey would remove this "feature". Of all the discussions that has gone on at AVS Forum and others, I've never remember reading where anyone thought it was a good thing. Also I don't know the other systems like Dirac etc like I do Audyssey, but I don't remember reading where any of them mess with rear channel levels dynamically with SPL?
Just don't make sense to me, but obviously someone at Audyssey did. LOL

In my personal experience, I've not seen Dirac Live try to boost the rear channels for lower volume.
Of course, with Dirac Live, if your AVR will hold several pre figured EQ curves that you can switch between, one could have one or more that boost an EQ band on one or more or all speakers. I have recently found that after running Dirac Live with it's multiple mic placements at different elevations about the listening position, adding the -6dB Harman curve helped the low end response. I don't have multiple subs, and my corners and center can get down fairly low, though the Dirac Live sets all the corners at 70Hz crossover and it works out. I can, and do, change that in pursuit of better for my tastes.
Dirac Live is not perfect, as is any room correction software I've used. But in my personal opinion it's pretty good and getting better.

 

[Sal1950]

Dirac Live is not perfect, as is any room correction software I've used. But in my personal opinion it's pretty good and getting better.

Right on. From the base Audyssey to it's TOTL MultiEQ-X, from the base Dirac to it's newest ART, and all the rest,
the final result is gonna depend more on the nut behind the configuration software than just about anything else.
I've been using the $20 Editor app running in Win10 Bluestacks andriod emulator software on my 32" monitor, and then doing some final checks with REW and a Umik2 and am quite pleased with the final results.
I am considering buying the $200 MultiEQ-X software since lately I've been having trouble connecting to the Denon with BlueStacks but I'd hate to spend the money only to find I still can't connect, that maybe the problem lies somewhere else.
My brain hurts lately.

 

[ssully]

I do agree that it's benefits are worth it's "bugs" but personally do find the changing of the rear balance annoying. I've tried to compensate for it by "re-adjusting" the rear levels but the fact that it is dynamic and changes with volume level makes it impossible to completely correct for.
I have for years hoped that the powers at Audyssey would remove this "feature". Of all the discussions that has gone on at AVS Forum and others, I've never remember reading where anyone thought it was a good thing. Also I don't know the other systems like Dirac etc like I do Audyssey, but I don't remember reading where any of them mess with rear channel levels dynamically with SPL?
Just don't make sense to me, but obviously someone at Audyssey did. LOL

I completely agree that the rear channel boost should be made an optional feature.

One thing I'm not 100% clear on: while the loudness compensation effect of DEQ changes with master volume, i.e., if you listen at the reference level, the DEQ compensation is zero, and increases gradually as you lower the MV, is the same shown to be true of the rear channel boost? I would think of course it must, but not sure.

 

[Sal1950]

I completely agree that the rear channel boost should be made an optional feature.

One thing I'm not 100% clear on: while the loudness compensation effect of DEQ changes with master volume, i.e., if you listen at the reference level, the DEQ compensation is zero, and increases gradually as you lower the MV, is the same shown to be true of the rear channel boost? I would think of course it must, but not sure.

If I follow you correctly, yes I believe your right on that.

 

[ssully]

If I follow you correctly, yes I believe your right on that.

If I'm right, the amount of rear channel boost also changes with master volume; at reference MV (equivalent to DEQ off), there would be no rear channel boost off.

 

[Sal1950]

If I'm right, the amount of rear channel boost also changes with master volume;

Yes, that the way I read it

at reference MV (equivalent to DEQ off), there would be no rear channel boost off.

I also believe that's true but without measurements I'm not 100% sure.

 

[Peeties]

Has someone with a dolby atmos setup in the AVR calibrate his/her room with a dolby atmos music target curve?

 

[mandrix]

Has someone with a dolby atmos setup in the AVR calibrate his/her room with a dolby atmos music target curve?

What is a dolby atmos target curve? I calibrate with Dirac Live for the sweet spot.

 

[jimfisheye]

Dolby Atmos is not skewed at all. There's no eq curve. The audio is 1:1 to the mix master. Tested it myself with my own mixes on day 1.

 

[mandrix]

The only EQ curves I add to my Dirac Live curves are the Harman -6 dB and -8 dB as Dirac seems to very conservatively raise the low end. Adding the Harman curves brings them more in line with my speakers.

 

[Peeties]

I will calibrate with Audyssey A1 Evo from OCA and have the choice of using a target curve;
What i have read about it that is curve is devolped in smaller cinema’s with dolby atmos with as base the x curve for very large cinema’s

 

[mandrix]

I guess I just don't understand the concept of having the AVR follow some target curve that may/may not be suitable for your audio room. I'm not going to say it's not viable since I've never seen it in use.
The whole point of calibration is to tailor your speaker response to your listening position(s). From there of course tweaks may be needed to suit your personal listening preferences.
I use multi point mic positioning with a UMIK-1 mic, and the Dirac Live pc software. Tweaks made afterward are mostly geared toward my personal preferences.
Are any of the calibration programs perfect? Probably not. But if you can get your speaker response/reflections dialed in it's a good start.

 

[Albert Dagger]

I guess I just don't understand the concept of having the AVR follow some target curve that may/may not be suitable for your audio room. I'm not going to say it's not viable since I've never seen it in use.
The whole point of calibration is to tailor your speaker response to your listening position(s). From there of course tweaks may be needed to suit your personal listening preferences.
I use multi point mic positioning with a UMIK-1 mic, and the Dirac Live pc software. Tweaks made afterward are mostly geared toward my personal preferences.
Are any of the calibration programs perfect? Probably not. But if you can get your speaker response/reflections dialed in it's a good start.

The main point of room correction software is to compensate for room modes below the Schroeder Frequency (200/300Hz) because it's hard to manage room modes via bass traps and absorption panels at home. Most home listening rooms can't look like cinema theatres and room correction can help any system with 2 or more channels. For surround systems, room correction is also useful to identify the correct level and distance of loudspeakers, and to correct the subwoofer response.

According to current literature, it's good practice to define a target curve with a low shelf of +5dB below 150Hz. That response feels natural. Correcting above the transition frequency (200/300Hz, sometimes up to 500Hz) seems detrimental because it changes the natural response of your speakers. Room correction should be turned off above that frequency using a curtain or similar command. It's better to use tone controls (EQ) if adjustments are required at higher frequencies. For example, in very reflective rooms, it could be useful to tone down the mid-range or treble.

 

[mandrix]

The main point of room correction software is to compensate for room modes below the Schroeder Frequency (200/300Hz) because it's hard to manage room modes via bass traps and absorption panels at home. Most home listening rooms can't look like cinema theatres and room correction can help any system with 2 or more channels. For surround systems, room correction is also useful to identify the correct level and distance of loudspeakers, and to correct the subwoofer response.

According to current literature, it's good practice to define a target curve with a low shelf of +5dB below 150Hz. That response feels natural. Correcting above the transition frequency (200/300Hz, sometimes up to 500Hz) seems detrimental because it changes the natural response of your speakers. Room correction should be turned off above that frequency using a curtain or similar command. It's better to use tone controls (EQ) if adjustments are required at higher frequencies. For example, in very reflective rooms, it could be useful to tone down the mid-range or treble.

Yes I know all that, I don't need a primer, thank you very much. I can manually adjust the curtains in the Dirac software, although it does a good job on it's own.
But going back to @Peeties post #47 I've never heard of a "Dolby Atmos Music Target Curve". So let us just go back to that. I'm not saying it's not a thing, just that I've never heard of it. So if someone could elaborate and what particular equipment uses it that would be cool.

 

[Albert Dagger]

Yes I know all that, I don't need a primer, thank you very much. I can manually adjust the curtains in the Dirac software, although it does a good job on it's own.
But going back to @Peeties post #47 I've never heard of a "Dolby Atmos Music Target Curve". So let us just go back to that. I'm not saying it's not a thing, just that I've never heard of it. So if someone could elaborate and what particular equipment uses it that would be cool.

I have no idea about what that is.
I think target curves work for single speakers regardless of the configuration.

 

[AudiophileStyle]

What is a dolby atmos target curve? I calibrate with Dirac Live for the sweet spot.

All DSP uses a target curve, even if it’s flat (I know that sounds silly, a flat curve). Within Dirac you can adjust the curve or even import target curves like the one below.

Here’s the Dolby Atmos Music target curve, straight from Dolby.

 

[AudiophileStyle]

The main point of room correction software is to compensate for room modes below the Schroeder Frequency (200/300Hz) because it's hard to manage room modes via bass traps and absorption panels at home. Most home listening rooms can't look like cinema theatres and room correction can help any system with 2 or more channels. For surround systems, room correction is also useful to identify the correct level and distance of loudspeakers, and to correct the subwoofer response.

According to current literature, it's good practice to define a target curve with a low shelf of +5dB below 150Hz. That response feels natural. Correcting above the transition frequency (200/300Hz, sometimes up to 500Hz) seems detrimental because it changes the natural response of your speakers. Room correction should be turned off above that frequency using a curtain or similar command. It's better to use tone controls (EQ) if adjustments are required at higher frequencies. For example, in very reflective rooms, it could be useful to tone down the mid-range or treble.

Based on my own research, experience using several room correction products, and talking to experts in the field, I believe some of your points are a bit incorrect if one is pursuing accurate sound reproduction. If one is shooting for what pleases them personally, not necessarily accurate, then all bets are off (absolutely nothing wrong with that).

Current state of the art room correction using 65,000 tap filters at 44.1/48, and scaling up with sample rate, created with Audiolense, work stunningly well when correcting the entire frequency spectrum. It sounds much better than partial correction in my experience.

 

[AudiophileStyle]

I guess I just don't understand the concept of having the AVR follow some target curve that may/may not be suitable for your audio room. I'm not going to say it's not viable since I've never seen it in use.
The whole point of calibration is to tailor your speaker response to your listening position(s). From there of course tweaks may be needed to suit your personal listening preferences.
I use multi point mic positioning with a UMIK-1 mic, and the Dirac Live pc software. Tweaks made afterward are mostly geared toward my personal preferences.
Are any of the calibration programs perfect? Probably not. But if you can get your speaker response/reflections dialed in it's a good start.

A target curve actually removes the room in a way. If every system used the same target curve, as measured at the listening position, we’d all hear the same thing (not accounting for hearing differences among us). Saying a curve may not work for a room, doesn’t really make sense because after DSP adjustments are made to follow the curve, the sound matches the curve. It doesn’t boost or lower frequencies no matter what, it’s all based on the listening position.

Every calibration uses a target curve. If a curve wasn’t used, it would have no idea which adjustments to make.

 

[mandrix]

A target curve actually removes the room in a way. If every system used the same target curve, as measured at the listening position, we’d all hear the same thing (not accounting for hearing differences among us). Saying a curve may not work for a room, doesn’t really make sense because after DSP adjustments are made to follow the curve, the sound matches the curve. It doesn’t boost or lower frequencies no matter what, it’s all based on the listening position.

Every calibration uses a target curve. If a curve wasn’t used, it would have no idea which adjustments to make.

I've read your posts and thank you for the explanation on the Dolby Target Curve, which is what I was after.
I understand target curves, as I have extensive experience (in my own home) with the Dirac Live pc app. But I did not do a good job stating so in the post you quoted. I misunderstood the intent of the post of Peetie as a sort of "one target curve fits all" sort of thing.
I do up to 13 mic placements in my audio room, although since I sit in one stationary position 5 would probably be plenty and I alone am the listener.

 

[mandrix]

I have no idea about what that is.
I think target curves work for single speakers regardless of the configuration.

Target curves can work for a single speaker or a group. e.g. If I make adjustments, I can group the fronts/rears/ tops or anyway I see fit. Or a single speaker.
When I add in the Harman curves I actually include all speakers, as the Dirac Live software seems fairly conservative on the low end. I can't recall offhand in this case exactly where the curtain is, in regards frequency, without looking at my calibrations but suffice to say I get the low end boost I desire.