Room EQ systems for AVP/AVR users thread

[AcuDefTechGuy]

I just want to be a little closer to ADTG's level.

You're already there, man.

 

[rnatalli]

Doesn't Dolby Leveler do anything to the FR like Dynamic EQ?

The Leveler is the equivalent to Dynamic Volume and the Modeler is equivalent to Dynamic EQ. I only engage the Modeler and it obviously affects the sound, but I have never measured it.

 

[PENG]

REW is amazingly useful, it even measures THD. Do Audyssey Pro and Anthem ARC measure THD ?

 

[rnatalli]

REW is amazingly useful, it even measures THD. Do Audyssey Pro and Anthem ARC measure THD ?

I don't see THD anywhere in the ARC software. Not sure about Audyssey Pro.

 

[PENG]

I don't see THD anywhere in the ARC software. Not sure about Audyssey Pro.

Well, there has to be a limit to what they could offer with the included RC system with their not excessively expensive AVRs. I suspect they may have a more advanced version for their high end processors. After playing with REW for a while, I am now fully convinced pure direct is really crap. I can post more graphs to show mine if anyone is interested. There is no point worrying about any minute distortions mainly due to electromagnetic interference, when the speakers and room interact in a violent way relatively speaking. I am also not a fan or Main+LFE, even Audyssey advised against that, sort of, if I remember reading correctly. Actually, REW or not, I don't remember when was the last time I used Pure Direct.


I just check out the Anthem website and found they now offer an ARC 1M for their AVRs. I may just have to get an MRX310 for my two channel system. It would have been great if they include their ARC in a lower end 2 channel preamp.

Are there 2 channel preamp out there that comes with a good RC system comparable to XT32 and AARC, excluding Emo?

 

[PENG]

Found this articlehttp://www.audioholics.com/loudspeaker-design/audio-measurements by Gene.

Looks like I am on the right track, that 1/12 octave smoothing is okay for analyzing, 1/3 is what most print and A/V magazines use and Audioholics uses 1/12.

 

[RichB]

I got rid of Pure Direct too



This measurement (1/6th) using the HA-1 DAC directly connect to the A51 taken at my listening position are a bit different than those I took months ago but that could be MIC positioning.

It is amazing how much variability there is by moving a foot in any direction.

Maybe we need a MIC that looks like one of those dummy heads with ears on both sides

- Rich

 

[PENG]

I got rid of Pure Direct too

View attachment 13883

This measurement (1/6th) using the HA-1 DAC directly connect to the A51 taken at my listening position are a bit different than those I took months ago but that could be MIC positioning.

It is amazing how much variability there is by moving a foot in any direction.

Maybe we need a MIC that looks like one of those dummy heads with ears on both sides

- Rich

In my room even a few inches made noticeable difference in the bass range. I also like the idea of mic that looks like dummy head with ears on both sides.

 

[AcuDefTechGuy]

Example of PD vs Reference vs Flat

This is from a Denon AVR2212, Audyssey XT, Red is Pure Direct, Green is Audyssey Reference, Blue is Audyssey Flat.

 

[AcuDefTechGuy]

In my room even a few inches made noticeable difference in the bass range. I also like the idea of mic that looks like dummy head with ears on both sides.

Does it vary greatly from 500Hz-20kHz from one listening position to another?

 

[RichB]

This is from a Denon AVR2212, Audyssey XT, Red is Pure Direct, Green is Audyssey Reference, Blue is Audyssey Flat.

That is interesting and looks like a good result.
The chart is hard to read but it looks like 8DB of boost at about 46hz and 5DB in the 2.5 to 3K area.

If I am reading it right, doesn't that translates into increased power requirements of something like 10x at 45hZ frequency and 2x in the mid-range?
So, is it reasonable to say that room correction can significantly increate power requirements?

- Rich

 

[AcuDefTechGuy]

That is interesting and looks like a good result.
The chart is hard to read but it looks like 8DB of boost at about 46hz and 5DB in the 2.5 to 3K area.

If I am reading it right, doesn't that translates into increased power requirements of something like 10x at 45hZ frequency and 2x in the mid-range?
So, is it reasonable to say that room correction can significantly increate power requirements?

- Rich

The way I see it, 75dB is the reference volume. So although Audyssey tries to flatten the FR curve, all the levels are still BELOW 75dB volume. And volume + distance dictates power requirement. So yes, an increase in volume does increase power requirement. But we only care about the final total reference volume level (80dB, 85dB, 90dB, etc.).

 

[PENG]

Does it vary greatly from 500Hz-20kHz from one listening position to another?

Rich is right to a point. That is probably one of the reasons why Audsysey and/or SVS PEQ only boost a few dB, probably no more than 3 dB. Audyssey does open up the throttle to boost more when DEQ is engaged, but remember DEQ is only effective from low volume to reference level, once Volume 0 is reached it will do NOTHING. So Rich is only right to a point.

In other cases it will seem like they boost more than a few dB even with DEQ off, but that's mainly the effect of fixing the room/time domain issue for example. If Audyssey were to boost as needed, you will have a flat curve all the time but you don't because the self imposed limit.

 

[RichB]

Rich is right to a point. That is probably one of the reasons why Audsysey and/or SVS PEQ only boost a few dB, probably no more than 3 dB. Audyssey does open up the throttle to boost more when DEQ is engaged, but remember DEQ is only effective from low volume to reference level, once Volume 0 is reached it will do NOTHING. So Rich is only right to a point.

In other cases it will seem like they boost more than a few dB even with DEQ off, but that's mainly the effect of fixing the room/time domain issue for example. If Audyssey were to boost as needed, you will have a flat curve all the time but you don't because the self imposed limit.

Was that a DEQ chart or just plain Audyssey?

- Rich

 

[PENG]

Was that a DEQ chart or just plain Audyssey?

- Rich

He didn't say but I am positive that it was just plain. If it was DEQ the bass range would have been elevated well above the pure direct one.

 

[RichB]

He didn't say but I am positive that it was just plain. If it was DEQ the bass range would have been elevated well above the pure direct one.

If it is plain Audyssey REQ, I suppose it could ramp down the correction in deference to the power requirements if it knew the AVR was power limited, but I doubt it.

EDIT: Of course, if REQ is taming bass humps, then you save power.

- Rich

 

[PENG]

So are there any two channel prepro or receiver that has a good Room EQ system build in for under 1K? I am hoping to use it with my A21/R900 two channel system so I don't have to listen to pure direct any more.

 

[RichB]

So are there any two channel prepro or receiver that has a good Room EQ system build in for under 1K? I am hoping to use it with my A21/R900 two channel system so I don't have to listen to pure direct any more.

J River's has DSP functions and there is PC based DIRAC prior combined with a DAC/Preamp.
DIRAC and miniDSP have a number of sub-1K products and they are also coming out with a DAC/DIRAC DSP.

- Rich

 

[PENG]

J River's has DSP functions and there is PC based DIRAC prior combined with a DAC/Preamp.

DIRAC and miniDSP have a number of sub-1K products and they are also coming out with a DAC/DIRAC DSP.

- Rich

The miniDSP digital in analog out seems to be what I need but the price with shipping is getting close to the MRX310. I am not sure if Dirac is better than AARC though.

 

[RichB]

The miniDSP digital in analog out seems to be what I need but the price with shipping is getting close to the MRX310. I am not sure if Dirac is better than AARC though.​

In the DIRAC series they have analog products which must do A/D conversion (which I am not advocating) but they have a lot of products now.

- Rich​