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#1 ·

I've been in several threads lately where the topic has been all about Audyssey and I've noted that there's not actually a thread specifically for it. There's one that seems to be about it, but it's titled as being about the Denon 3806. Audyssey, of course, exists in far more receivers than the 3806 nowadays, so I thought I'd throw a starter into the pool to see if people were interested in having one thread to discuss all Audyssey issues/comments/questions/stories/impressions that they've come up with from their personal receiver-experiences.


Myself, i was quite anti-Audyssey when I first came across it. My ears were quite used to what they'd had before which was very bass & treble heavy. Time has passed and I've really come to understand the strengths of Audyssey and respect the clean, flat signal that I now love and enjoy (and couldn't imagine being without). I'd love to hear from anyone else that wants to chime in or discuss issues.


Basic starter-links:


The Audyssey homepage .


The types of Audyssey implimentations in different receivers.



The Audyssey FAQ


The Audyssey setup guide


====

Audyssey tips:

Microphone Placement


The microphone has been calibrated for grazing incidence and so it must point to the ceiling during calibration. Any other orientation will produce incorrect results.


The microphone response has been calibrated to match (on average) the response of an industry-standard ¼ instrumentation microphone. It is critical to use the microphone that came with the receiver and not one from another model that may have a different calibration curve.


It is also important to place the microphone on a tripod or other stand so that it is at ear height. We strongly recommend against holding the microphone in your hand because this can give rise to low frequency handling noise that will cause the MultEQ filters to compensate by cutting those frequencies. Furthermore, it is not recommended to place the microphone on the back of the couch or recliner. If a tripod is used, care must be taken to ensure that the microphone is placed at a height just above the seat back so that reflections from the seat do not cause problems at higher frequencies.


The first microphone position is used to calculate the distances to each loudspeaker and subwoofer and set the delays. It is also used to measure and set the trims. So, it is important to place the microphone in the main listening seat for the first measurement.


MultEQ measures the background noise level in the room before playing the test signal from each speaker. For the measurements to be valid, the signal to noise ratio must be above a certain threshold. If it is not, the test signal from that speaker will repeat at a higher level. If the noise in the room happens to be higher during some of the speaker measurements, then the test signals from those speakers will sound louder than the test signals from the other speakers. This does not affect the calculation of trim levels. If the room noise is too high even after the test signals increase in level, then an error message will be displayed warning the user that measurements can not be completed.


After the first position is measured, MultEQ measures other positions in the room around the listening area. These do not necessarily have to be in each individual seat. The idea is to capture as many points around the listening area as possible so that the acoustical problems that affect the quality of sound within that area are minimized.


For example, we recommend taking 3 positions on the couch facing the TV and then 3 more positions about 3 feet in front of the couch and parallel to the first three. Measurements up against the back or side walls should be avoided.


Some loudspeakers have rather problematic responses when measured off-axis (i.e. more than 15° away from the imaginary straight line that points to the listening position). In these systems, measurements taken too far away from the center line will show a reduced high-frequency response that may result in overcorrection and thus overly bright sound. Although it is difficult to predict which type of loudspeaker will have these off-axis problems we have most often observed them in poorly-designed multiple-driver arrays that exhibit very high off-axis lobing. In these situations we recommend a tighter calibration pattern centered around the main listening position and making sure that the mic is not placed in extreme locations and certainly not outside the plane of the front main speakers.

Checking the Results


Once MultEQ calibration is complete the results are stored in the receiver memory.


It is important to activate MultEQ by selecting one of the target curves. This is not performed by default after the calibration is finished and must be selected by the user. In a THX system we recommend using the Flat setting that allows the re-equalization to work as intended. In other systems, we recommend Audyssey for movie playback and Flat for music playback. Unfortunately, the music industry does not have any mixing standards like the movie industry so some music program material may sound better with the Audyssey setting. Front Align also uses the Audyssey process, but it does not apply the filters to the two front loudspeakers. Manual is not an Audyssey setting and does not use MultEQ filters. It is a simple parametric equalizer and will be subject to all the limitations that come with parametric EQ.


Small vs. Large speakers. This is the most commonly discussed topic by MultEQ users. The first thing to understand is that it is not a personal insult to your system if your speakers were detected as Small. It simply means, that in the room they were measured the - 3 dB point was detected at 80 Hz or above. This may happen even if the manufacturer's spec shows that the speaker is capable of playing lower. In fact, there are several benefits at crossing the speakers over at 80 Hz that have to do with power handling and headroom in the bass region that will be handled by the subwoofer amplifier.


The second most common question also relates to Small vs. Large. In the Denon receivers, MultEQ will designate as Large any speaker that has a -3 dB point below 80 Hz. For non-THX speaker systems this is an arbitrary definition that often causes confusion. All it means is that the speaker will not be bass managed unless the user tells it to be. Because Audyssey is not in charge of bass management, we have to abide by the manufacturers' rules and simply report the information found by the measurements to the bass management system.


In situations where the speakers do not play significantly below 80 Hz, an additional step must be taken to make sure that there is no loss of bass information. The user must set the speaker to Small manually so that bass management is performed properly.


Polarity: MultEQ checks the absolute polarity of each loudspeaker and reports it to the user. This is simply a report and does not affect the subsequent calculations in any way. It just asks you to check the wiring to make sure it is connected properly to each speaker. Sometimes we get false alarms. This is usually because the speaker has a driver (usually the mid-range driver) wired out-of-phase intentionally to make up for some problems at the crossover region. If a phase warning is shown, it is not a cause of alarm. Simply check the cables and hit Skip if everything is fine. Again, this does not have any effect on the EQ results.


Subwoofer distance: in many active subwoofers it is not possible to defeat the low-pass filtering. That means that the pre-pro bass management filters will be on top of the low-pass filters inside the subwoofer. The built-in low-filters introduce a delay to the signal coming in (because they have poles). This delay is seen by MultEQ as acoustical delay and is reported in the results. That is why sometimes the subwoofer distance is reported to be longer than the physical measured distance. The setting should not be changed because the blend between the sub and the satellites has been designed based on this time delay.


The design constraints for MultEQ were that it (1) must fit within a small portion of the DSP so that other processes can also run and (2) it must use FIR filters because of the well-known artifacts that IIR filters cause particularly in the time domain response. As it turns out, these two requirements are contradicting. In order for FIR filters to be effective and capable of correcting to low frequencies, they must consist of several thousand coefficients (taps). The problem is that the CPU power required increases with the number of taps, hence the dilemma. What we did at Audyssey was to come up with a different way to partition the frequency axis so that we can use fewer taps and yet not completely give up on low frequency resolution (and therefore low frequency correction). This allows us to take a 512 tap filter that would normally have a resolution of 94 Hz (meaning that any peak or dip narrower than 94 Hz would be missed) and significantly improve its resolving power. The resolution of the filter actually varies continuously with frequency and starts at around 10 Hz. Does this mean that MultEQ can correct an arbitrarily narrow peak or dip at 30 Hz? Of course not. The reality is that in the MultEQ XT version found in receivers, we can correct broader features below 100 Hz better than narrow ones. For example, a lump that is half an octave wide at 50 Hz can be fixed. A narrow dip or peak that is 1/3 or 1/6 octaves wide and centered at 30 Hz will be improved, but not eliminated.


The on-screen display in the receiver has very limited graphics. Therefore it is not possible to really show what the MultEQ correction filter is doing at all frequencies. It appears to only be operating on 9 bands like a parametric equalizer, but this is not the case. What is shown is a very crude approximation to the MultEQ correction and it should not be used to read exact values of cut or boost at the 9 frequencies shown.


Furthermore, there is no display for the subwoofer filter. This doesn't mean that there is no subwoofer correction. It was not added to the display because of interface and memory considerations.


(tips by Chris, CTO, Audyssey Laboratories)
 
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#51,642 ·

Quote:
Originally Posted by allsop4now /forum/post/21773400


I recently bought a Denon 2312 to replace an aging Onkyo with the useless EQ2. The XT made a real improvement, I'm happy to say, but getting a grip on the differences on XT and XT32 is hard (apart from the attractive dual sub EQ feature).
See below for a link to my version of the advantages of XT32 over XT.


Some claim that XT32 do not adjust higher frequencies as much as XT, but that is anectodes.
IIRC someone posted some measurements indicating clustering of filter points in the lower freqs of the sats in this thread.


I got the upgrade bug but still are not convinced about XT32 for my 5.1 setup in a medium sized room (EU style)...

XT32 is a significant advance IMO, see this post . But we don't know anything about your room or system. I recommend upgrading the weakest link in your HT sound chain with the overall objective of matching the quality of everything, such as the electronics to the speakers. Got good speakers? A second sub carefully placed to smooth the bass is also a valuable addition if you have not done so, regardless of XT32. I also recommend doing what's practical to fix the acoustics in your room (curtains, rug, formal acoustic tx like bass traps, etc.).
 
#51,643 ·

Quote:
Originally Posted by kbarnes701 /forum/post/21773024


Hi Harrison. I agree with most of your post, except for this bit.


Assuming a 'reasonable' room, the aim of Audyssey is to deliver the Audyssey target curve so long as one follows the instructions - ie if the mic is placed at ear height, pointing up, spaced at about 2 feet distance for measurements, within the boundaries defined by the front speakers, 2 feet away from walls etc etc.


If one follows those instructions it is possible to get what we might call Result A. But one can then do a different measurement, using different mic positions - but still within Audyssey's guidelines - and get instead Result B. This would suggest to me that the system is not 'perfected'.


Clearly, different mic positions will yield different results - and that is the problem. One can follow Audyssey's instructions very precisely but get two different results. If the system was perfect, following their instructions would deliver the target curve every time.


Not that any of this matters very much - it is just of academic interest IMO. I have found that I get excellent results every time by following the guidelines in the Setup Guide. But I can get different, excellent results if I move the mic about a bit.

While you are correct that different mic positions will give different results, given a reasonable room and target bubble and the guideline number of measurements, the differences in those results will be modest. Nonethelss, if one understands well enough how the system works and wishes to do several sets of mic positions and keep the one they like best, the software will do that. It's perfect
for that.


Maybe we are really talking about the number of mic locations. And I think we are talking about folks that are going well beyond the Audyssey guidelines. You mentioned two foot spacing and that is the rub. A lot can be going on between those two-foot mic locations. Since we are talking about "the software" I think we are talking about a pro-install with up to 32 measurements available. In this case one is not limited to two foot spacing.


A user that is worried about different sets of mic positions should use all 32 measurements even if the bubble is just two seats. This would address all frequency response problems (deviations from flat) in the bubble as best as is possible because few deviations from flat would be missed. That would be getting pretty close to perfect
in my book. Surely it would be better than multiple sets of measurements with fewer mic positions.


There is no limit on how close the mic positions can be. I used to duplicate measurements around my head just to favor my seat since my wife is less particular about SQ. I have also done a circle around where my head would be with six or eight mic positions. Then I figured out that it was smarter to do single mic position runs around my two-seat bubble to see what problems existed. That gave me a head start on the pattern that would be most effective. The pro software (and system) is perfect
for this.


Now that I know what the frequency response problems are around the two seats in my living-room based HT, I know that I only need seven measurements to have virtually optimum frequency response. I take #1 in the center of my head, #'s 2, 3 to either side of my head by 6 or 8 inches and #4 8" in front of my face. I do a similar triangle around my wife's head for #'s 5, 6, and 7. The software was perfect in providing me the needed information to reduce my mic positions and identify the best ones.



The improvement I get from this seven measurement result over a more conventional pattern is not large though I do avoid a couple of bumps that are not present in the smaller pattern.


BTW, if there were major issues in my wife's seat that would reflect into my seat I would probably be doing just one seat.



Would a pattern of three mic positions around each of 10 or 11 seats in a room that is not much larger than that 10 or 11 seat listening bubble work well? It would work and likely provide some improvement, but it's just not possible to dramatically improve a whole room. If I had this situation I would, as others have suggested, focus on the most used seats.


Yes, it may take some ingenuity and experimentation, but the software can do about as perfect
a job as can be done within the constraints of the hardware and laws of physics.


Hope I read your comments correctly.


Harrison

EDIT eh, I just noticed jmschnur's post ... He said what I said above in about 8 words!
 
#51,645 ·

Quote:
Originally Posted by craig john /forum/post/21770749


Hi Feri,


Below is a set of measurements taken at the Kansas City Blind Subwoofer Meet. These were taken after running Audyssey on each sub. The subs were placed in the same positions and the mic positions were ostensibly the same. If we were truly "confident that Audyssey is striving to set the low end flat", wouldn't we expect that all of these subs would truly be *flat* after being EQ'd/Room Corrected by Audyssey?


http://www.avsforum.com/avs-vb/showthread.php?t=1387178

(Graph is in Post #3)


Yet, they are anything BUT flat. More importantly, they are all *different*! How do you explain that?


Craig

Hi Craig, thanks for sharing that info. Wish I were there!



About the graphs. Although they are not ruler flat but they seem to follow the same trend down to 20 Hz where things seem to start to change quite a bit. As the video embeded into that thread explained, these graphs are averages of multiple mic position measurements, but we already know from Chris K. that REW, Omnimic, etc. can only do RMS averaging, i.e. no weighting of "problems" are done. But when it comes to Audyssey's secret elixir we also know that Audyssey puts emphasis on more common problems in the listening area with its clustering, weighting and fuzzy logic way of processing each of the mic measurements into one final filter response.


And IMHO since our human hearing perceives sound waves differently than a test mic, I think the most interesting (though proprietary) solution Audyssey came out with it the way how to translate that into the psychoacoustic domain.


Or as Jeff (pepar) used to say: measured flatness and perceptual flatness are two different things...so I still wish I was there in Kansas to hear the show...
 
#51,646 ·

Quote:
Originally Posted by veger69 /forum/post/21773152


Well I have always had those types of inclinations whether it is cars or computers or Music but maybe if I had a more direct question. I'm most interested in tweaking the XO and evaluating the Phase control Knob settings on my LFM-1 EX. As far as speaker setup goes integrating a SW into my system has always given me the most trouble. It would be nice to have a tool to take some of the guess work out of it. I'm ready for school! Learning new tech has always been a hobby for me.

Dang, we agree on that .... cars, computers and music.


Improving the sub-satellite blending is a key feature of the Audyssey system. The higher the grade of Audyssey the better the blending. At the upper limit is the Pro Install kit for receivers that can accommodate it. It takes sub setup and blending to another level.


The first page of this forum contains recommendations on setting the sub phase and getting a good blend. That should be your first stop. Then back here with any questions.


Harrison


Harrison
 
#51,647 ·
Hi again. Again I tend to agree with most of your post, other than the bit I don't agree with


Quote:
Originally Posted by hclarkx /forum/post/21773764


Maybe we are really talking about the number of mic locations. And I think we are talking about folks that are going well beyond the Audyssey guidelines. You mentioned two foot spacing and that is the rub. A lot can be going on between those two-foot mic locations.

I said two feet apart because that is what Audyssey's instructions say. ( http://www.audyssey.com/audio-technology/multeq/how-to ). My point was that even when following Audyssey's instructions one can still get two different results depending on mic placement - but always within their instructions. That's why I say it isn't perfect. If it was perfect it would always give the same result if one followed the instructions. It is because "a lot can be going on between those two-foot mic locations" that this situation arises.


Quote:
Originally Posted by hclarkx /forum/post/21773764


Since we are talking about "the software" I think we are talking about a pro-install with up to 32 measurements available. In this case one is not limited to two foot spacing.

I was actually talking about the consumer MultEQ so maybe we are at cross-purposes. HST, Audyssey still say to use two foot spacings even when using the 32 potential positions of Pro software - the same link as above refers.


I think that the fact that there are some 52,000 posts in this thread shows that setting up Audyssey is as much an art as a science - a black art possibly
. Your own setup procedure, while clearly very effective for you, is miles from what Audyssey say is needed, and again, I put that forward as evidence that it is from from 'perfect'.
 
#51,648 ·

Quote:
Originally Posted by kbarnes701 /forum/post/0



Don't touch that sub distance setting!!



When Audyssey says it is setting 'distance', it is really setting 'delay'. The idea is that Audyssey will know the distance of each speaker from the mic (in position 1) and it will then be able to set delays so that all the sound arrives at the MLP at the same time.


But the sub is a special case. The sub has its own internal processing (as part of its amplifier settings and controls etc) and so Audyssey has to take account of any delays that this internal processing causes. Thus it will usually set the sub distance to greater than the physical distance of the sub from the MLP (the greater the distance, the sooner Audyssey has to 'start' the signal, thus overcoming the internal delay caused by the sub's own processing).


Note that Audyssey is not setting the distance for any effect at all on the loudness of the sub at the MLP. That's a separate thing and you are doing the calibration correctly from what you say. If you want to increase the loudness of the sub after calibration, it is OK to change the trim level - just don't touch the distance setting at all.

Sorry I am replying to this so late, Keith. There has been extensive discussion earlier in this thread regarding adjusting the sub distances to achieve the smoothest transition at the crossover point. I agree that one should not adjust the sub distance simply because the Audyssey calculated distance is different than the physical distance. But there is a precedent for adjusting distances, carefully measuring the results with something like REW or OmniMic, to improve the sound quality.
 
#51,649 ·

Quote:
Originally Posted by hclarkx /forum/post/0



Dang, we agree on that .... cars, computers and music.


Improving the sub-satellite blending is a key feature of the Audyssey system. The higher the grade of Audyssey the better the blending. At the upper limit is the Pro Install kit for receivers that can accommodate it. It takes sub setup and blending to another level.


The first page of this forum contains recommendations on setting the sub phase and getting a good blend. That should be your first stop. Then back here with any questions.


Harrison


Harrison

Thanks Harrison

I have a Denon AVR 2903ci with Audyssey MultiEq XT. I do not believe my receiver is compatible with the pro kit.
 
#51,650 ·

Quote:
Originally Posted by AustinJerry /forum/post/21773881


Sorry I am replying to this so late, Keith. There has been extensive discussion earlier in this thread regarding adjusting the sub distances to achieve the smoothest transition at the crossover point. I agree that one should not adjust the sub distance simply because the Audyssey calculated distance is different than the physical distance. But there is a precedent for adjusting distances, carefully measuring the results with something like REW or OmniMic, to improve the sound quality.

I agree, AJ. But see my reply to Jeff about this. The OP is a novice and fiddling with sub distances to improve his splice is miles away from where he currently is at, which is why I ignored it. His question was very basic - should he trust the Audyssey measured distance or change it back to 'reality'. The best advice for him in those circs and with his admitted level of knowledge, is, IMO, to leave the sub distance where Audyssey put it. His real problem was 'boominess' in his bass and this almost certainly has nothing to do with the splice or the sub distance set by Audyssey - it's probably DEQ messing him about (he was using music for evaluation not movies) or maybe some problem inherent in his room. Also, as you suggest, if one is going to mess with the sub distance to try to improve the splice, one also needs REW or OmniMic etc - and I am pretty sure the OP does not have such tools available to him.
 
#51,651 ·

Quote:
Originally Posted by cavchameleon /forum/post/21773836


Harrison,


I have done from 8 - all 32 positions in my room (which is pretty symmetrical and treated) and found that there is a point of diminishing returns, at least in my room. I now settle with 20 positions.

Not Harrison, but care to expand a bit on "point of diminishing returns"?
 
#51,653 ·

Quote:
Originally Posted by mogorf /forum/post/21773909


Not Harrison, but care to expand a bit on "point of diminishing returns"?

As mentioned I tried many different mic positions, starting with a minimum of 8 and the full 32 positions. There did not seem to be anything different in the graphs after I went above 15 positions (in my room) and it really did not sound any different with more. I still did 20 just to have a good sampling of the seating area as in my diagram. At one point I actually did 15 (remove the ones not on the couch) and added another 15 in the same spots, but 5 inches above. Again, the results did not seem that different than the original 15.
 
#51,654 ·

Quote:
Originally Posted by kbarnes701 /forum/post/0



I agree, AJ. But see my reply to Jeff about this. The OP is a novice and fiddling with sub distances to improve his splice is miles away from where he currently is at, which is why I ignored it. His question was very basic - should he trust the Audyssey measured distance or change it back to 'reality'. The best advice for him in those circs and with his admitted level of knowledge, is, IMO, to leave the sub distance where Audyssey put it. His real problem was 'boominess' in his bass and this almost certainly has nothing to do with the splice or the sub distance set by Audyssey - it's probably DEQ messing him about (he was using music for evaluation not movies) or maybe some problem inherent in his room. Also, as you suggest, if one is going to mess with the sub distance to try to improve the splice, one also needs REW or OmniMic etc - and I am pretty sure the OP does not have such tools available to him.

I agree with you, Keith. One of the challenges we face in this thread is to assess a poster's level of expertise and target the response accordingly. If we were to somehow be able to assemble the incredible amount of knowledge in this thread into an Audyssey FAQ, then both the basic and advanced aspects of a topic could be presented. I continue to respect the valuable advice that you provide to the new thread participants!
 
#51,655 ·

Quote:
Originally Posted by kbarnes701 /forum/post/21773901


Also, as you suggest, if one is going to mess with the sub distance to try to improve the splice, one also needs REW or OmniMic etc - and I am pretty sure the OP does not have such tools available to him.

Keith, ...or as another option we can use our own ears as well. I've just recently come to the conclusion how superb microphones our ears can be when it comes to tweaking such delicate issues like the XO splice. Warning: deep water, swimmers only!
 
#51,659 ·

Quote:
Originally Posted by veger69 /forum/post/0



Thanks Harrison

I have a Denon AVR 2903ci with Audyssey MultiEq XT. I do not believe my receiver is compatible with the pro kit.

Correct although it was more bad memory than typo 2809ci
 
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