I posted much of this information on AVS's Audyssey Pro forum, but thought I would add it here as well.
Over the past few weeks, I have been on an "adventure" figuring out channel level settings on my Denon AVR-A100. What is easy for most folks (no brainer) turned out to be an issue for me, because I have an 11.2 system using a combination of 4 Klipschorns, a Belle Klipsch center and 6 Heresy IIIs - all high efficiency speakers.
When I got the AVR-A100 a little over a year ago, I ran XT-32 and noticed that the Klipschorns and Belle channel levels were set at -12 with the Heresys about 5-6 db above that. The system sounded fine, so I left it alone.
In January of this year, I bought Audyssey Pro. As you know, it made quite a bit of difference in overall sound. Again, with the K'horns, the channel levels bottomed out, but the system sounded great - or so I thought. I left DEQ on and tried mid comp on and off, and decided I liked it off.
I got the bug to add external amps and run the Denon in preamp mode. I went well over the top power wise and added two Emotiva XPA-5s and a UPA-1 mono block for center. The Emotivas have higher gain than some amps, so this made my channel level problems worse. After running 'Pro again and then checking relative channel levels with a RS meter, they were way off. When I manually brought them to match, there was a huge difference in volume between DEQ on and off. Plus, the surrounds were much too loud with DEQ on.
After a few posts on the AVS Audyssey Pro forum, I was convinced that for DEQ to work properly, all channels have to be within the Denon's channel level adjustment range. Manual adjustment just screwed the DEQ up and that was apparently why the surrounds were way too high after manual matching.
Soooo, I ordered 12db attenuators for the 5 K'horn and Belle channels. Levels after running 'Pro again were -2 to -3, so with the Emotivas I was 14 to 15 db off calibration. Then I noticed that 'Pro had set the side Heresys to -12. I had a pair of 6db attenuators and put them in those channels to make sure everything was within the Denon's adjustment range.
So, what did all this do for me? The system sounds more fantastic than ever before. No volume change between DEQ on and off. The system is no longer too bright. Surround envelopment is more cohesive.
I know that many folks won't have this problem, but for owners of high efficiency speakers, check to see if your channel levels are bottomed out. Of course, with the internal amps in the AVR, there is not much you can do about it. But if you are using external amps, the attenuators are very much worthwhile. Here are the ones I bought:
http://www.amazon.com/Harrison-Labs...bs-Line-Level-Attenuator/dp/B0006N41B0/ref=sr_1_2?ie=UTF8&qid=1338030825&sr=8-2
They are availabe as 3db, 6db, and 12db for the same cost. Parts Express has some that are much less expensive, but the reviews on them are not favorable.
Over the past few weeks, I have been on an "adventure" figuring out channel level settings on my Denon AVR-A100. What is easy for most folks (no brainer) turned out to be an issue for me, because I have an 11.2 system using a combination of 4 Klipschorns, a Belle Klipsch center and 6 Heresy IIIs - all high efficiency speakers.
When I got the AVR-A100 a little over a year ago, I ran XT-32 and noticed that the Klipschorns and Belle channel levels were set at -12 with the Heresys about 5-6 db above that. The system sounded fine, so I left it alone.
In January of this year, I bought Audyssey Pro. As you know, it made quite a bit of difference in overall sound. Again, with the K'horns, the channel levels bottomed out, but the system sounded great - or so I thought. I left DEQ on and tried mid comp on and off, and decided I liked it off.
I got the bug to add external amps and run the Denon in preamp mode. I went well over the top power wise and added two Emotiva XPA-5s and a UPA-1 mono block for center. The Emotivas have higher gain than some amps, so this made my channel level problems worse. After running 'Pro again and then checking relative channel levels with a RS meter, they were way off. When I manually brought them to match, there was a huge difference in volume between DEQ on and off. Plus, the surrounds were much too loud with DEQ on.
After a few posts on the AVS Audyssey Pro forum, I was convinced that for DEQ to work properly, all channels have to be within the Denon's channel level adjustment range. Manual adjustment just screwed the DEQ up and that was apparently why the surrounds were way too high after manual matching.
Soooo, I ordered 12db attenuators for the 5 K'horn and Belle channels. Levels after running 'Pro again were -2 to -3, so with the Emotivas I was 14 to 15 db off calibration. Then I noticed that 'Pro had set the side Heresys to -12. I had a pair of 6db attenuators and put them in those channels to make sure everything was within the Denon's adjustment range.
So, what did all this do for me? The system sounds more fantastic than ever before. No volume change between DEQ on and off. The system is no longer too bright. Surround envelopment is more cohesive.
I know that many folks won't have this problem, but for owners of high efficiency speakers, check to see if your channel levels are bottomed out. Of course, with the internal amps in the AVR, there is not much you can do about it. But if you are using external amps, the attenuators are very much worthwhile. Here are the ones I bought:
http://www.amazon.com/Harrison-Labs...bs-Line-Level-Attenuator/dp/B0006N41B0/ref=sr_1_2?ie=UTF8&qid=1338030825&sr=8-2
They are availabe as 3db, 6db, and 12db for the same cost. Parts Express has some that are much less expensive, but the reviews on them are not favorable.