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"Official" Audyssey thread (FAQ in post #1) - Page 1998

post #59911 of 62239
2/15/13 at 10:16am
Fwiw I remember vaguely that there may have been a bug in some recent onkyos that messed up low frequency correction. There was slso a crazy one msybe four years ago in which denon's software caused incorrect reporting of the test results and caused a very significant low frequency error. Maybe we could add a grnersl reference that if one's receiver seems to behave contrary to the expected there is a possibility of software problems.
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post #59912 of 62239
2/15/13 at 11:37am
Quote:
Originally Posted by AustinJerry View Post

Quote:
Originally Posted by Wryker View Post


When you say "measure" are you referring to using an SPL meter? I'm in the process of changing out my rear-surrounds and after that I'll be running Audyssey again. I do have an SPL meter.

 

If you re-read Igor's posting, the measurement is taken from the pre-outs.  By toggling Audyssey off and on, you can see exactly what is happening without the influence of the listening room.  For example, here is a pre-out measurement of my left speaker, one without Audyssey and one with XT32 applied.

 

 

In this example, you see Audyssey correction down all the way to 20Hz because Audyssey sets my speakers to "Large", i.e. the F3 point is probably below 30Hz.  (Actually 30Hz, +/- 3dB on axis, according to the manufacturer)

Jerry, how exactly do you take a pre-out measurement?  I'm curious to figure out why Audyssey XT32 is setting the crossovers of my surrounds to 40Hz?  I suppose it could be room effects but I guess I would've expected the opposite (i.e. a higher crossover setting)?

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post #59913 of 62239
2/15/13 at 12:21pm
Quote:
Originally Posted by jkasanic View Post

Quote:
Originally Posted by AustinJerry View Post

Quote:
Originally Posted by Wryker View Post


When you say "measure" are you referring to using an SPL meter? I'm in the process of changing out my rear-surrounds and after that I'll be running Audyssey again. I do have an SPL meter.

 

If you re-read Igor's posting, the measurement is taken from the pre-outs.  By toggling Audyssey off and on, you can see exactly what is happening without the influence of the listening room.  For example, here is a pre-out measurement of my left speaker, one without Audyssey and one with XT32 applied.

 

 

In this example, you see Audyssey correction down all the way to 20Hz because Audyssey sets my speakers to "Large", i.e. the F3 point is probably below 30Hz.  (Actually 30Hz, +/- 3dB on axis, according to the manufacturer)

Jerry, how exactly do you take a pre-out measurement?  I'm curious to figure out why Audyssey XT32 is setting the crossovers of my surrounds to 40Hz?  I suppose it could be room effects but I guess I would've expected the opposite (i.e. a higher crossover setting)?

 

Well, I haven't tried this since we started experimenting with USB mics for REW.  With the legacy REW setup, you would connect an audio cable from the Pre-out connection on the back of the AVR and connect it to the Input side of the sound card in place of the mic.

 

For the new REW setup, I don't know how this would work.  I'll post a question on HTS.

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post #59914 of 62239
2/15/13 at 1:20pm
Quote:

Originally Posted by AustinJerry View Post

 

Well, I haven't tried this since we started experimenting with USB mics for REW.  With the legacy REW setup, you would connect an audio cable from the Pre-out connection on the back of the AVR and connect it to the Input side of the sound card in place of the mic.

 

For the new REW setup, I don't know how this would work.  I'll post a question on HTS.

 

Thanks!

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post #59915 of 62239
2/15/13 at 4:24pm
I have read all the faq. on Audysses and have a ? I have the Onkyo Sc5508 and I am trying to run XT32. I set the PB2/Ultra with crossover disabled and the sub sonic filters to bypass and phase to 0. Is this correct? Do I leave the 20hz setting and 1 port plugged or do I set it to bypass and take the plug out when running XT32? Thanks for your help.
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post #59916 of 62239
2/15/13 at 4:48pm
Question about Audyssey Pro (which will work with my AVR): The kit is selling for $550. Does that include a single license of the purchaser? And how much do additional licenses cost?
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post #59917 of 62239
2/15/13 at 4:49pm
Quote:
Originally Posted by jkasanic View Post

Jerry, how exactly do you take a pre-out measurement?  I'm curious to figure out why Audyssey XT32 is setting the crossovers of my surrounds to 40Hz?  I suppose it could be room effects but I guess I would've expected the opposite (i.e. a higher crossover setting)?
generally speaker specs are based on an anechoic environment. doesn't get any tougher. put em in a room with walls that bounce sound and low end can't reasonably go down from zero bounce, but can potentially go up.
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post #59918 of 62239
2/15/13 at 4:50pm
Price does not include license.
$150 is approx the cost.
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post #59919 of 62239
2/15/13 at 5:32pm
Quote:
Originally Posted by kbarnes701 View Post

The FAQ reflects Audyssey's own view of how it works and it does seem to work that way for the majority of users. I can't really change the FAQ to reflect anecdotal evidence from a small number of people whose credentials are unknown to me.

Unfortunately it seems the Audyssey's point of view has changed at some point (silently) and now they think it should correct the slope under F3 to achieve 4th order roll off there. It still doen't explain my case as it still boosts considerably more than is needed to get 4th order roll-off at the detected frequency. And once they start doing the correction below F3 they should take into account the original natural roll off also when estimating F3 as any room mode extending the F3 down the frequency will require boosting heavily everything below it to build a roll off from lower frequency than the natural one.

I understand your feelings after you had so mush experience with Audyssey and it newer happened before, it might sound to you anecdotal, but it is same feeling for me, when I see the measurements, the contradiction with a FAQ, which claims are totally logical and rational, while the measurements are totally out of place. It is completely repeatable on any of my speakers detected starting from 40Hz for fronts, ending at 60Hz for surrounds, or even 120Hz when the bi-pole surrounds are free-standing and not on their usual places. I asked to measure a new owner of 818 on russian forum to measure his pre-outs to compare, his unit bought half a year later than mine, in different country (mine was bought is Germany), and he confirmed he also have this one-and-a-half octave +10dB boost. The only similarity between our setups is the room sizes - 3m*5.6m (sorry I am bad in American units) - quite common room size here and our walls are from concrete. So, after that it really feels anecdotal to me there are so many admiring reports about SQ of the 818, especially with XT32, and nobody notice the increased distortion... I can believe that it is not noticeable to everyone, but really there should be more users who are affected and disappointed as it reduces the headroom of the amps/speakers by 10dB basically in many setups, and the IM distortion is also bigger, as high frequencies are modulated by higher amplitude low frequency signal... If I didn't hear this myself I wouldn't start investigating it further and finally get to those measurements that pretty much confirm everything I hear with my ears.
Quote:
Originally Posted by kbarnes701 View Post

What I can do is add a footnote to that section saying that some people have found this or that. If you would suggest some wording, I will certainly consider that as I know you are not the only one saying what you are saying.

Yes, this is exactly what I expected. The wording could be something like "There is an evidence that Audyssey XT32 can boost bellow F3, sometimes very heavily (+10dB), that might create problems for some users limiting headroom of their setups. The problem is only confirmed by some user measurements of Onkyo TX-NR818 at the moment, but there was no any evidence if it can happen to other receivers with XT32. The problem is happening for satellite channels and doesn't happen to the subwoofer channel and not related to the old normalization bug." I remember there also was a footnote about normalization bug in sub channel somewhere in FAQ, at that time many users here complained... Surely you can correct my crappy English wording smile.gif
Quote:
Originally Posted by kbarnes701 
smile.gif What is your first language Igor? In English a lie is the deliberate telling of the opposite of the truth. In the case we are discussing, it would perhaps be an 'error' or a 'mistake'.
No offence taken BTW - I know how difficult it can be to have in-depth technical discussions in a foreign language.
I am Russian, living in Estonia.
And... it is not error or mistake either, I believe it is the right way, how it should work smile.gif But it just appears that it works differently in real life, so, while it is right it is not true. At least sometimes, or with some specific receivers... There is no enough statistics to tell precisely when and where, the only we can tell at the moment is that it works differently on Onkyo 818 that may lead to inferior calibration.
Quote:
Originally Posted by kbarnes701 
You may be the only one who cares about it, but do others acknowledge that it exists? Do Onkyo or Audyssey say it exists?
After two months of sending mails back and forth between Onkyo support and me they finally passed it to someone technical and he promised me to do try to reproduce it during a week, I replied that I will try to be as helpful as possible, then the third week is coming and he is not responded and not answering anymore frown.gif
After some talk with Chris at AskAudyssey here, he replied "We have been unable to reproduce this." and AskAudyssey is closed for comments now frown.gif

But the fact is - the first independent person agreed to measure his 818 in his not so ideal room was able to reproduce this immediately...
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post #59920 of 62239
2/16/13 at 3:20am
Quote:
Originally Posted by IgorZep View Post

Quote:
Originally Posted by kbarnes701 View Post

The FAQ reflects Audyssey's own view of how it works and it does seem to work that way for the majority of users. I can't really change the FAQ to reflect anecdotal evidence from a small number of people whose credentials are unknown to me.

Unfortunately it seems the Audyssey's point of view has changed at some point (silently) and now they think it should correct the slope under F3 to achieve 4th order roll off there. It still doen't explain my case as it still boosts considerably more than is needed to get 4th order roll-off at the detected frequency. And once they start doing the correction below F3 they should take into account the original natural roll off also when estimating F3 as any room mode extending the F3 down the frequency will require boosting heavily everything below it to build a roll off from lower frequency than the natural one.

I understand your feelings after you had so mush experience with Audyssey and it newer happened before, it might sound to you anecdotal, but it is same feeling for me, when I see the measurements, the contradiction with a FAQ, which claims are totally logical and rational, while the measurements are totally out of place. It is completely repeatable on any of my speakers detected starting from 40Hz for fronts, ending at 60Hz for surrounds, or even 120Hz when the bi-pole surrounds are free-standing and not on their usual places. I asked to measure a new owner of 818 on russian forum to measure his pre-outs to compare, his unit bought half a year later than mine, in different country (mine was bought is Germany), and he confirmed he also have this one-and-a-half octave +10dB boost. The only similarity between our setups is the room sizes - 3m*5.6m (sorry I am bad in American units) - quite common room size here and our walls are from concrete. So, after that it really feels anecdotal to me there are so many admiring reports about SQ of the 818, especially with XT32, and nobody notice the increased distortion... I can believe that it is not noticeable to everyone, but really there should be more users who are affected and disappointed as it reduces the headroom of the amps/speakers by 10dB basically in many setups, and the IM distortion is also bigger, as high frequencies are modulated by higher amplitude low frequency signal... If I didn't hear this myself I wouldn't start investigating it further and finally get to those measurements that pretty much confirm everything I hear with my ears.
Quote:
Originally Posted by kbarnes701 View Post

What I can do is add a footnote to that section saying that some people have found this or that. If you would suggest some wording, I will certainly consider that as I know you are not the only one saying what you are saying.

Yes, this is exactly what I expected. The wording could be something like "There is an evidence that Audyssey XT32 can boost bellow F3, sometimes very heavily (+10dB), that might create problems for some users limiting headroom of their setups. The problem is only confirmed by some user measurements of Onkyo TX-NR818 at the moment, but there was no any evidence if it can happen to other receivers with XT32. The problem is happening for satellite channels and doesn't happen to the subwoofer channel and not related to the old normalization bug." I remember there also was a footnote about normalization bug in sub channel somewhere in FAQ, at that time many users here complained... Surely you can correct my crappy English wording smile.gif
Quote:
Originally Posted by kbarnes701 
smile.gif What is your first language Igor? In English a lie is the deliberate telling of the opposite of the truth. In the case we are discussing, it would perhaps be an 'error' or a 'mistake'.
No offence taken BTW - I know how difficult it can be to have in-depth technical discussions in a foreign language.
I am Russian, living in Estonia.
And... it is not error or mistake either, I believe it is the right way, how it should work smile.gif But it just appears that it works differently in real life, so, while it is right it is not true. At least sometimes, or with some specific receivers... There is no enough statistics to tell precisely when and where, the only we can tell at the moment is that it works differently on Onkyo 818 that may lead to inferior calibration.
Quote:
Originally Posted by kbarnes701 
You may be the only one who cares about it, but do others acknowledge that it exists? Do Onkyo or Audyssey say it exists?
After two months of sending mails back and forth between Onkyo support and me they finally passed it to someone technical and he promised me to do try to reproduce it during a week, I replied that I will try to be as helpful as possible, then the third week is coming and he is not responded and not answering anymore frown.gif
After some talk with Chris at AskAudyssey here, he replied "We have been unable to reproduce this." and AskAudyssey is closed for comments now frown.gif

But the fact is - the first independent person agreed to measure his 818 in his not so ideal room was able to reproduce this immediately...

 

Igor - thanks for the detailed explanation and for your continuing efforts to get to the bottom of the problem you describe. Also, thank you for the suggested wording for a footnote in the FAQ. I will add such a footnote later in connection with the 818, with the caveat that Audyssey say they cannot reproduce the problem, but also with the comment that you are still trying to pursue them for an answer. 

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post #59921 of 62239
2/16/13 at 6:51am
Quote:
Originally Posted by pbarach View Post

Question about Audyssey Pro (which will work with my AVR): The kit is selling for $550. Does that include a single license of the purchaser? And how much do additional licenses cost?
Nope $550 is just the kit. You'll need one $150 license for each processor you want to calibrate with the Pro kit. That license is permanently attached to that unit, is non-transferable to another unit and the key to the license expires every 30 days-but can be easily and quickly be renewed online for free indefinitely. You'd only need an additional license if you have more than one processor or buy a new processor.

Lots more great info in the Pro Kit FAQ that Keith assembled in the Pro Kit thread (FAQ also linked in his sig).

edit-corrected
Edited by SoundofMind - 2/16/13 at 9:04am
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post #59922 of 62239
2/16/13 at 8:37am
OK, the license doesn't expire - ever. But one needs to use the Pro Installer site to generate a "key" that is entered when the Pro (software) initially "logs onto" the unit to be calibrated. The key expires every 30 day and that is what needs to be refreshed/regenerated. It's free and easy, but obviously one needs internet access to do it.

Jeff
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post #59923 of 62239
2/17/13 at 1:39am
I believe the issue Igor is talking about is the level normalization. This has been discussed and documented in this thread and occurs only under specific circumstances.

If there are many peaks in the FR, Audyssey may need to apply a lot of cuts to EQ the FR, and in order to normalize the levels back to the calibrated levels, the normalization is applied with a boost across the spectrum and occasionally results in up to a 10db boost below the F3, which can bottom out the subs.



Max
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post #59924 of 62239
2/17/13 at 2:27am
Quote:
Originally Posted by djbluemax1 View Post

I believe the issue Igor is talking about is the level normalization. This has been discussed and documented in this thread and occurs only under specific circumstances.

If there are many peaks in the FR, Audyssey may need to apply a lot of cuts to EQ the FR, and in order to normalize the levels back to the calibrated levels, the normalization is applied with a boost across the spectrum and occasionally results in up to a 10db boost below the F3, which can bottom out the subs.

Max

It's probably worth stressing that normalization and equalization are independent: norm sets the intended dB level (which eq'ing respects), and many peaks "fool" the norm process into setting too high a level.
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post #59925 of 62239
2/17/13 at 4:35am
Quote:
Originally Posted by djbluemax1 View Post

I believe the issue Igor is talking about is the level normalization. This has been discussed and documented in this thread and occurs only under specific circumstances.

If there are many peaks in the FR, Audyssey may need to apply a lot of cuts to EQ the FR, and in order to normalize the levels back to the calibrated levels, the normalization is applied with a boost across the spectrum and occasionally results in up to a 10db boost below the F3, which can bottom out the subs.

Your belief is wrong. It is not normalization, as the frequency response drops back down under this one-and-a-half octave under F3. Also if you think small untreated room with concrete walls at home is something very specific - you are wrong, only a small fraction of those receivers are used in large rooms with proper treatments, and nowhere in the docs it is mentioned the calibration can only work correctly in properly treated rooms, quite the contrary to that. That one problem with subwoofers and normalization also was quite frequent. Only small portion was complaining just because most are not measuring their systems. This normalization problem for subwoofer channel was solved and fixed on that receivers long time ago, and I verified it is not present on my setup with my subwoofer.

The problem I am describing is with satellite channels, it leads basically to the same sonic problems, and more as it is with full-range channel and bottoming out / distorting also affects how high frequencies sound, but the reason of this boost is different. I am too was thinking about returning of normalization problem but to main channels, but measurements on lower frequencies show it is not the case.
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post #59926 of 62239
2/17/13 at 10:46am
Interesting. But what makes you think it's not normalization? If the graph you posted is of the pre-out measurements and not in-room, you can see that Audyssey has applied a lot of cutting between 50Hz and 7kHz. I can't recall the region that the software uses for normalization, but IIRC, it might have been somewhere between 100Hz and 1kHz to 2kHz.

If that's the case, Audyssey would see the cuts in that region and boost everything to normalize. This could explain why the region below 50Hz 'appears' to have been boosted, because it is un'EQd as it is below the detected F3 and thus has no cut applied, but the normalization boost has increased their levels relatively.

If that's a pre-out graph, it looks similar to the pre-out graphs of systems suffering the normalization boost below F3 problem.

Keep us posted on what Audyssey or Onkyo has to say.


Max
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post #59927 of 62239
2/17/13 at 12:11pm
Quote:
Originally Posted by djbluemax1 View Post

But what makes you think it's not normalization?
The answer is in my first sentence: "the frequency response drops back down under this one-and-a-half octave under F3". I have no graphs at hands to show it for lower frequencies, but even on the graph I posted you can see the frequency response goes back down below 20 Hz.
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post #59928 of 62239
2/17/13 at 12:49pm
Quote:
Originally Posted by djbluemax1 View Post

If that's the case, Audyssey would see the cuts in that region and boost everything to normalize. This could explain why the region below 50Hz 'appears' to have been boosted, because it is un'EQd as it is below the detected F3 and thus has no cut applied, but the normalization boost has increased their levels relatively.

Whatever it is, the word 'appears' is not right there as it tries to excuse this boost, when there could be no excuses for it. The way how it was treated with normalization of sub channel - i.e. the fix was made to the firmwares of affected units to take normalization process under control so it doen't cause the boost was the right solution to the problem from which all won. Now we have another problem, but again with the effect of heavy boosting under F3, seems Audyssey is not learning from their mistakes frown.gif

Also, if you think this +10dB is the base level to what EQ cuts/boosts was applied then try to point to something above F3 in my graph that wasn't cut... There will be nothing, obviously.
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post #59929 of 62239
2/17/13 at 5:19pm
It appears that the language barrier is causing problems with your comprehension. Nowhere in my post have I said or indicated that there is an excuse for anything. I'm simply explaining how the problem can be caused and how to interprete what you're seeing from the measurement graph. I'm inclined to think most of our native English speaking posters understood my explanation.

Whatever the case may be, I've said my piece. Feel free to rail away.


Max
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post #59930 of 62239
2/17/13 at 6:44pm
I miss Feri.
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post #59931 of 62239
2/17/13 at 7:18pm
Quote:
Originally Posted by pepar View Post

I miss Feri.

 

eek.gif

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post #59932 of 62239
2/18/13 at 3:39am
Quote:
Originally Posted by djbluemax1 View Post

It appears that the language barrier is causing problems with your comprehension. Nowhere in my post have I said or indicated that there is an excuse for anything.
Sorry for misunderstanding, I just got so many replies already in the past telling that this is something that just look like boost, but it is not the boost. As the word appears also have meaning of 'looks like' I read it in this meaning instead of 'caused from that'. Anyway it is not normalization and I already explained what confirms it. If it would be the normalization the graphs would show this boost indefinitely down the frequency to the single digit Hz.
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post #59933 of 62239
2/18/13 at 3:55am
Quote:
Originally Posted by kbarnes701 View Post

Quote:
Originally Posted by IgorZep View Post

Quote:
Originally Posted by kbarnes701 View Post

What I can do is add a footnote to that section saying that some people have found this or that. If you would suggest some wording, I will certainly consider that as I know you are not the only one saying what you are saying.

Yes, this is exactly what I expected. The wording could be something like "There is an evidence that Audyssey XT32 can boost bellow F3, sometimes very heavily (+10dB), that might create problems for some users limiting headroom of their setups. The problem is only confirmed by some user measurements of Onkyo TX-NR818 at the moment, but there was no any evidence if it can happen to other receivers with XT32. The problem is happening for satellite channels and doesn't happen to the subwoofer channel and not related to the old normalization bug." I remember there also was a footnote about normalization bug in sub channel somewhere in FAQ, at that time many users here complained... Surely you can correct my crappy English wording smile.gif

 

Igor - I have added a Technical Note to the FAQ answer we discussed above, using your wording as the basis.

 

c)2.   Why do I often see advice to raise the Crossovers to 80Hz?

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post #59934 of 62239
2/18/13 at 3:57am
Quote:
Originally Posted by pepar View Post

I miss Feri.

 

Try adjusting your sights and breathing out slowly... :)

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post #59935 of 62239
2/18/13 at 5:16am
Quote:
Originally Posted by kbarnes701 View Post

Igor - I have added a Technical Note to the FAQ answer we discussed above, using your wording as the basis.

Looks great! Thank you very much.
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post #59936 of 62239
2/18/13 at 5:30am
Quote:
Originally Posted by IgorZep View Post

Quote:
Originally Posted by kbarnes701 View Post

Igor - I have added a Technical Note to the FAQ answer we discussed above, using your wording as the basis.

Looks great! Thank you very much.

 

You are welcome. Thanks for bringing the issue to our attention.

 

I forgot to credit you with raising the issue - I have done so now at the end of the Technical Note.

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post #59937 of 62239
2/18/13 at 7:37am
Quote:
As for the sib trim showing up between ±3 dB, that's one of those internet myths that is going around. That level adjustment is just a relative number that makes sure your sub is playing at the same level as the other speakers. It will depend on where you set the analog volume control on the back of your sub.

This quote is from Audyssey Zendesk . I about fell off my couch when I saw this quote. He also says that your sub volume should be turned up to 50% and should only be turned down if you get a -12 level on your sub. He suggest keeping your volume on your sub the same, even if you get a -11db level on the sub. So, is the +/-3db subwoofer level a myth?
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post #59938 of 62239
2/18/13 at 8:19am
As Chris wrote, "that makes sure your sub is playing at the same level as the other speakers." just like all levels for all the other speakers. Note that he said nothing about auto-on sensitivity, which has always been my personal reason for wanting to have a reasonably high signal level driving the subwoofer. Different models of plate-amps are bound to have slightly different auto-on sensitivity thresholds. After all, you don't really want a subwoofer turning on when low level noise has been picked up by the cabling.
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post #59939 of 62239
2/18/13 at 8:26am
I thought u adjust the volume control until it read 75dbs and then continue with the rest of the calibration, I had to bypass the LFE input on my sub ( using the LFE input bypasses all controls ) and I would not have a way to adjust the volume on the sub so I use the left or right input and the volume control is set to 1.5 out of 12 to reach 75dbs and after calibration my sub trims are at -3.5. I would assume if I adjusted the sub volume control to 4-5 then my trims would be around -7 or -9 so as long as your not at -12 it really should not matter, but then again I could be wrong.
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post #59940 of 62239
2/18/13 at 8:50am
Quote:
Originally Posted by sojodave View Post

Quote:
As for the sib trim showing up between ±3 dB, that's one of those internet myths that is going around. That level adjustment is just a relative number that makes sure your sub is playing at the same level as the other speakers. It will depend on where you set the analog volume control on the back of your sub.

This quote is from Audyssey Zendesk . I about fell off my couch when I saw this quote. He also says that your sub volume should be turned up to 50% and should only be turned down if you get a -12 level on your sub. He suggest keeping your volume on your sub the same, even if you get a -11db level on the sub. So, is the +/-3db subwoofer level a myth?

 

The Technical Note in this FAQ answer has some additional insights:

 

f)3.    How do I set the controls on my subwoofer before running MultEQ?

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AVS › AVS Forum › Audio › Receivers, Amps, and Processors › "Official" Audyssey thread (FAQ in post #1)