Audyssey

[Donald]

I've tried to find literature with a little more detail about what Audyssey can do in the way of room and speaker equalization. Some of the posts here show measurements that indicate that there are not very many eq bands available (perhaps only octave intervals). Does anyone have any better information, or know of any data showing a comparison between the Denon Receiver type Audyssey and a standard 1/3 octave graphic, or 5 band parametric approach? Denon has not been helpful, although they did say they might publish a white paper at some time.

Donald

[Sonnie]

Hi Donald and welcome to the Shack!

The Audyssey website has a pretty good tutorial of what the MultEQ actually does.

The Audyssey is going to do all the measuring and choosing of specific filters for you vs. you have to measure and only have 1/3 octave filters to choose from on a graphic EQ. The graphic EQ bandwith/Q will not be adjustable, whereas the MultEQ will adjust itself as needed.

Some others here might be able to get more technical with an explanation.

[Kal Rubinson]

Donald wrote:

Some of the posts here show measurements that indicate that there are not very many eq bands available (perhaps only octave intervals).

That is untrue. What confuses some is that Denon approximates very roughly what Audyssey EQ is doing because the Denon lacks the display capabilities and because Audyssey does not reveal its results quantitatively.

The Audyssey thread on AVS is lively, (mostly) informative and has the participation of one of the Audyssey developers.

Kal

[MatrixDweller]

I just bought a Denon 2808ci that has Audyssey MultEQ XT. I had upgraded from a Denon 3805 which has an auto parametric EQ feature. Audyssey does a lot more.

My first try with Audyssey pointed out a phase problem in my front right speaker. A friend that works in a audio store had made me some cables that had one set of banana plus on one end and two on the other so to bi-wire. IMO bi-wiring does nothing but they were free so what the hey. Anyway he had hooked them up for me 6 months ago and I thought things sounded fine. When I looked on the back I could see that the woofer was in phase put the tweeter was reversed. The 2808 picked that up but the 3805 did not.

After correcting the phase problem I completed the tests for one position. My first impression was...where the heck did the bass go. The center channel also sounded very bright.

Further inspection revealed that the sub was turned down to -12dB and it set the distance at 16 ft. Actual tape measure distance was 9.4 feet. Audyssey had also set my fronts as large and the center and surrounds as small. I have 4 Klipsch RB81 and a RC62 center. I'd figure the surrounds being the same make and model should register the same. It pegged the crossover for the RB61's at 60Hz (they are rated down to 46Hz by Klipsch). It set the center at 80Hz and it's rated to 54Hz by Klipsch so fairly accurate IMO.

I ran the MultEQ again with 3 positions. The sub was still set low (pretty much muted) but after adjusting the channel level things started to sound better. I also adjusted the center channel level slightly up and set all speakers to small and the sub to LFE+Main. I'm still not 100% happy with the sound and the bass is inconsistent. Some scenes it's over powering where as in others it's hardly there as opposed to being at a nice level on the 3805.

I'm going to redo the MulEQ setup this weekend for 8 positions. I'll also be sure to set the crossovers and LFE differently. My current room is not the best. One side is open and the other is a solid wall. The measurements are about 10x12 (listening area) but with the open side it really extend out to more like 10x24. There are no acoustic treatments other than the couch and carpet.

I will post my opinion after I've done the tests again.

[MatrixDweller]

After configuring the Denon 2808ci for 8 positions it did the following.

It set the Surrounds and Center at 40Hz
Set the fronts to 60Hz
Set the distance correctly to all speakers except the sub which was about 5 feet off.
Set the subwoofer level at -12dB.
Edit: It set all speakers to small this time.

Conclusion: Audyssey does not accurately capture the subwoofer. This seems to be the resounding conclusion of many other people that have posted to AVS Forum and other sites.

Of course my room shape and size might have something to do with that but I'm still not 100% impressed by the sound of the bass even after adjusting it manually. I upped the crossover level of the Surrounds to 60Hz and the Center to 80Hz and that made a small improvement. I'd have to get a SPL meter and do some graphs to really get a feel for what's going on. I'm hoping when I move my gear into the, still under construction, basement dedicated theater room things will change for the better.

The one thing I do notice with Audyssey is that the surround field does sound very nice. I would say that it sounds better than my old 3805 in that department. Though the lack of AL24+ processing on all channels and a lesser DAC on the 2808 hurt it in other places.

It would be nice to hear how well (or not) Audyssey works on the 3808 or 4308 as well as on the Onkyo 805 and 875 and others.

[RNRGAGNE]

That's one of the biggest myths, or misunderstandings of Audyssey; that it doesn't capture the sub right. People like yourself are misled by incorrect sub distance set by the Audyssey. This is a deliberate thing that Audyssey does to compensate for phase & time alignment. It shouldn't be messed with unless it's ridiculous like 20ft off. If it's running your sub at -12db you should probably turn it down before running the Audyssey.
It is important that it gets the speaker distances correct however, if it doesn't try again.

I run a line array infinite baffle sub with 4X 15" drivers and two Rythmik Audio 12" Servo sealed subs in-line with my mains. The Audyssey XT did an absolutely excellent job with my bass.

[RNRGAGNE]

I should add that I used to run an SMS-1 with my IB, and the Audyssey actually produces better results despite the fact that I had the sub dialed in very flat with the SMS.

[MatrixDweller]

RNRGAGNE wrote:

This is a deliberate thing that Audyssey does to compensate for phase & time alignment. It shouldn't be messed with unless it's ridiculous like 20ft off. If it's running your sub at -12db you should probably turn it down before running the Audyssey.

Initially I didn't think anything of the level being set at -12dB. It was that I couldn't hear any base. It was like taking a bass knob and turning it down all the way. The fact that Audyssey set the distance differently I can understand as it probably has to do with my room layout and sub placement.

The fact that it set it at -12dB and that it is barely audible should have nothing to do with how loud I had the sub while testing. Audyssey should adjust it accordingly no matter what volume it's at. Again it's probably because my room is less than ideal. I made sure to set the subwoofer to 0 dB increase on my RW12d when testing. The RW12d, not the best sub I admit, goes down to -40dB and up to +11dB. Would having it 0dB be correct?

I'm sure a closed rectangular room with somewhat ideal measurements is probably going to give test measurements that yield better over results. Little anomalies in room acoustics are probably fixed easily by Audyssey but large ones are probably a more difficult and might skew things for the worst. My sub is in a corner, and I can't place it anywhere else due to room layout, so that is probably why things are messed up.

[Kal Rubinson]

RNRGAGNE wrote:

That's one of the biggest myths, or misunderstandings of Audyssey; that it doesn't capture the sub right. People like yourself are misled by incorrect sub distance set by the Audyssey. This is a deliberate thing that Audyssey does to compensate for phase & time alignment. It shouldn't be messed with unless it's ridiculous like 20ft off. If it's running your sub at -12db you should probably turn it down before running the Audyssey.
It is important that it gets the speaker distances correct however, if it doesn't try again.

I run a line array infinite baffle sub with 4X 15" drivers and two Rythmik Audio 12" Servo sealed subs in-line with my mains. The Audyssey XT did an absolutely excellent job with my bass.

Yes and the other big issue is that folks are adapted to and may prefer BIG bass rather than flat bass. It may take some re-adaptation.

Kal

[RNRGAGNE]

MatrixDweller wrote:

Initially I didn't think anything of the level being set at -12dB. It was that I couldn't hear any base. It was like taking a bass knob and turning it down all the way. The fact that Audyssey set the distance differently I can understand as it probably has to do with my room layout and sub placement.

The fact that it set it at -12dB and that it is barely audible should have nothing to do with how loud I had the sub while testing. Audyssey should adjust it accordingly no matter what volume it's at. Again it's probably because my room is less than ideal. I made sure to set the subwoofer to 0 dB increase on my RW12d when testing. The RW12d, not the best sub I admit, goes down to -40dB and up to +11dB. Would having it 0dB be correct?

I'm sure a closed rectangular room with somewhat ideal measurements is probably going to give test measurements that yield better over results. Little anomalies in room acoustics are probably fixed easily by Audyssey but large ones are probably a more difficult and might skew things for the worst. My sub is in a corner, and I can't place it anywhere else due to room layout, so that is probably why things are messed up.

Well there's a lot of reasons that it could have your sub too low, but 12db is a huge cut which just seems to indicate that it's too loud to begin with. Audyssey no doubt has to compute how many db it has to work with for the entire system and then adjust accordingly. Whether it be Audyssey or any room EQ you want to get everything as close to right as possible before running it.

Generally the subs' volume should be set about halfway. That will allow enough headroom if the Audyssey decides to boost any frequencies. Also corner loading a sub produces the most amount of bass, but can also produce that "boomyness" that Kal reiterated to. You could be very used to bloated bass.

You're right Audyssey isn't the fix-all for a really bad room but usually it will do more good than harm and its strength IMO is the bass.

Maybe you could post some pics of your room taken from the first measurement position and from the center channel back to the listening position. There night be some simple things you could do to get better results.

[MatrixDweller]

My avatar is a picture somewhat taken from the primary listening position. I know the room is really bad and I am building a dedicated room in my basement. I'll take a couple better shots and post them so that you can have a laugh.

BTW: I think I was 90% done the dedicated room in November, but the wife had "other" plans for me and my paycheck. Conservatively it's looking like March it will be done. The agony

[RNRGAGNE]

Well it's better than my agony. I open up my crawlspace to build my dedicated HT and someone dropped a dime to the city thinking I was building a secondary suite. Long story short, looks like I'll be filling it back in...

[MatrixDweller]

Heheh...maybe the "dime dropper" can help supervise the fill in (from within the crawlspace).