Audessey professional calibration worth every penny - Page 11 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #301 of 394 Old 10-12-2009, 09:23 AM
AVS Special Member
 
audioguy's Avatar
 
Join Date: Jun 2001
Location: Not far from Atlanta - but far enough!
Posts: 3,596
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 473 Post(s)
Liked: 336
Audyssey will tell you there is NO two channel reference. There are a set of standards for movies that the director may or may not follow and it is that standard to which Audyssey strives.

Having installed hundreds of two channel digital room correction systems (not Audyssey), in 99% of the cases, there was no harm done. In a very few of the cases the improvement may or may not have justified the expense but in every other case, there were major improvements. And the listening environments were from very high end speakers in family rooms (no treatment) to dedicated listening rooms with appropriate treatment.

In virtually all of these cases, the digital signal from the CD transport went to the correction system and then was converted to analog either by our product or an external DAC.

Audyssey or even Audyssey Pro will work perfectly fine for most (and that is a key word) environments but in those cases where it does not work well, there may not be enough flexibility even in Audyssey Pro to make it work. And I can assure you that the flexibility required to adapt the product to those more complex room situations implies product complexity and most folks don't really have the acoustic (or mathematical) knowledge to properly use such a system.

As I have stated previously, there are more flexible products on the market that cost 10 times more.

As to what an appropriate target curve might be, there are a couple of approaches. The one we used that provided the best results was to design a curve that had the general shape of the FR at the listening position without correction --- and with the knowledge (from manufacturers spec) of what the low end extension was.Audyssey determines low end cut off based upon the 3db down spot which, in some cases is NOT the correct low end extension point if there happens to be an anomolie in the room that could create that size null. As an example, all Dunlavy speakers have about a 4db roll-off from 10K to 20K at the listening position (not in an anechoic chamber) and we built that roll-off into our target curve. When we used a flat target curve, the sound would become fatiguing with some material.

Audyssey for the price and functionality is a no brainer. If it doesn't work in your environment, there are other much more expensive solutions.

New Theater

Don't count the years. Make the years count. Lou Holtz
audioguy is online now  
Sponsored Links
Advertisement
 
post #302 of 394 Old 10-12-2009, 09:24 AM
AVS Special Member
 
coldmachine's Avatar
 
Join Date: Nov 2006
Location: Waiting in the weeds
Posts: 5,807
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Rabident...I agree that the DynamicEQ idea was, and is, actually very sound and is based on solid scientific fact.

I found the implementation didn't live up to the promise. I did find Dolby Volume to be clearly superior. There are some caveats to that, the "music" algorithm being one.

--------------------------------------------
"Wow, do you think you are Adonis"...... "Baby, I'm not A-donis, I'm THE-donis"
coldmachine is offline  
post #303 of 394 Old 10-12-2009, 10:18 AM
AVS Addicted Member
 
Kal Rubinson's Avatar
 
Join Date: Mar 2004
Location: NYC + Connecticut
Posts: 28,525
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 132 Post(s)
Liked: 163
Quote:
Originally Posted by SierraMikeBravo View Post

I should think it would be the nearfield environment (that being the response without effects of the room) of the "actual" speaker you have in your room provided there are no serious fequency response problems with the speaker itself would you not agree? Isn't that what we are striving for at the listening position itself minus the room effects and the natural rolloff due to the attenuation of high frequency energy with distance?

Thanks for taking the bait.

That near-field FR is something the listener was not supposed to hear and that we never listen to. (Well, some might.) Nearfield responses may not benefit from the proper blending of multiple drivers. Speakers are designed to be listened to in an acoustical environment which, with consequent difficulty, is not fixed or defined. I am not trying to be critical you or of any particular response but to raise for discussion the question of what is our goal. For me, it is the correct FR at my listening position, taking into account all the equipment, speakers and room effects, such that it results in as accurate as possible recreation of the original event. IMHO, nothing after the actual performance is completely free of human manipulation and, therefore, is not sacrosanct.

Quote:


Isn't that WHY we are calibrating in the first place, and when did I say it it can never be violated? I just said if you don't mind it being changed. Some do, some don't.

Sure but I do not see why there should be an issue at all.

Kal Rubinson

"Music in the Round"
Senior Contributing Editor, Stereophile
http://www.stereophile.com/category/music-round

Kal Rubinson is online now  
post #304 of 394 Old 10-12-2009, 10:55 AM
AVS Special Member
 
hifisponge's Avatar
 
Join Date: Jan 2004
Location: Redmond, WA
Posts: 7,516
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
Quote:
Originally Posted by Kal Rubinson View Post

For me, it is the correct FR at my listening position, taking into account all the equipment, speakers and room effects, such that it results in as accurate as possible recreation of the original event. IMHO, nothing after the actual performance is completely free of human manipulation and, therefore, is not sacrosanct.

What do you believe the target curve to be to achieve "correct FR" at the listening position? How do you know that the target you chose will give you an "accurate recreation of the original event" if there is no standard? When measuring, how much wieght is put on direct vs reflected sound?
hifisponge is offline  
post #305 of 394 Old 10-12-2009, 11:22 AM
AVS Special Member
 
hd_newbie's Avatar
 
Join Date: Jun 2008
Location: Metro DC
Posts: 2,088
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
Quote:
Originally Posted by broke_ht_nut View Post

I posed this question by email to both Auddyssey and Trinnov and both gave me the same answer. They said that it was not recommended to layer eq systems and both said to disengage other eq systems before using their products.

Would you mind copy-pasting that response in the thread?
hd_newbie is offline  
post #306 of 394 Old 10-12-2009, 11:51 AM
AVS Addicted Member
 
noah katz's Avatar
 
Join Date: Apr 1999
Location: Mountain View, CA USA
Posts: 20,816
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 422 Post(s)
Liked: 189
"It turns out the well known characteristic of human hearing where bass needs to be louder at lower listening levels to be perceived the same as it is at reference wasn't included as part of the original Audyssey correction algorithm. DynamicEQ fixes that.

A whole group of naysayers were outright dismissed as bass heads that didn't like reference sound, but the introduction of DynamicEQ means those same people were actually right. They were hearing flaws in Audyssey's implementation (below reference level)."

That doesn't wash - there was no DynamicEQ before they used Audyssey, nor does it seem to be a complaint w/other EQ systems.

Noah
noah katz is offline  
post #307 of 394 Old 10-12-2009, 11:56 AM
AVS Addicted Member
 
Kal Rubinson's Avatar
 
Join Date: Mar 2004
Location: NYC + Connecticut
Posts: 28,525
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 132 Post(s)
Liked: 163
Quote:
Originally Posted by hifisponge View Post

What do you believe the target curve to be to achieve "correct FR" at the listening position? How do you know that the target you chose will give you an "accurate recreation of the original event" if there is no standard?

There are several answers. First, the target curve depends on the presumptions of the mastering engineers and, while there is some consensus with movies, there is none with music recordings. Second, in view of that, I can only try to make the response through my system flat (or, for movies, a bit rolled off) to minimize its influence. Third, your very questions support my argument that those who think that changing the FR is a violation of principle are ignoring all the variable influences encumbered by a home system/room.

Quote:


When measuring, how much wieght is put on direct vs reflected sound?

That is hard to encompass in a single measurement and is greatly influenced by the speaker design. I like wide-dispersion speakers in an acoustically treated room but I have no quantitative information to offer you.

Kal Rubinson

"Music in the Round"
Senior Contributing Editor, Stereophile
http://www.stereophile.com/category/music-round

Kal Rubinson is online now  
post #308 of 394 Old 10-12-2009, 03:55 PM
AVS Special Member
 
filecat13's Avatar
 
Join Date: Jul 2003
Location: SoCal
Posts: 4,507
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 25 Post(s)
Liked: 92
Quote:
Originally Posted by Kal Rubinson View Post

There are several answers.


That is hard to encompass in a single measurement...

Ah, well, there it is. Unlike the fiction of Neo in The Matrix or other fantasized universal solutions in movies, literature, and religion about "The One," there is no unity of perfection in the studio or sound reproduction realm. In fact, the idea that a single standard of perfection can be attained through science and technology is rendered moot by the very fundamental, unscientific, mystic roots of faith (or gullibility) necessary for perfection to exist as a concept.

We have amazing tools that are more sophisticated with each successive generation that bring us both closer to the ideal and also to the realization that the ideal is far too relative to ever be unified. Neither my ideal nor my judgement/belief on perfection will ever be the same as someone else's, and vice-versa.

In fact, for some folks, the more the masses embrace something as being ideal (often meaning "good enough"), the more those folks who want to be "special" or who have very high expectations seek to distance themselves and their aspirations from those of the masses. That's one reason why snake oil products enjoy such celebrity in some segments of the audio world.

It's all compromise in the end. "How much compromise is enough?" is the real question. Let me pull some figures out of my @$$ here.

50% think MP3s players, car radios, DVDs, TVs, and all-in-one stereos are good enough.
25% think CDs, DVDs, flat panel TVs, surround receivers, and HTIB are good enough.
10% think CDs. DVDs, 720p flat panels displays, high end receivers with auto EQ, and big box retail surround speaker systems are good enough.
5% think SACD, DVD-A, Bluray, 1080p flat panels, pre/pros with auto EQ, separate amps, bass traps, big name brand front speakers and bookshelf surrounds are good enough.
5% think vinyl and stereo (no video) are good enough.
3% think SACD, DVD-A, Bluray, 1080p flat panels, pre/pros with auto EQ, separate amps, some passive room treatment (drapes, carpet, maybe bass traps) big name brand front speakers and name brand bookshelf surrounds are good enough for HT ,and vinyl and stereo are good enough for music.
1% don't listen to anything.
.75% think that complete, custom-designed, multi-channel, high end solutions in dedicated and treated rooms are good enough.
.25% are on forums like these, shockingly close to the realization that it may never be good enough.

So, I'd postulate that Audessey PRO and other fairly sophisticated approaches far exceed the expectations of 90%+ of the available audience, and that it will never meet the expectations of at least 1%.

As for me, I'm PDH with my little Synthesis® set up and calibration, and I believe that I'd be thrilled with a great Audessey PRO set up, too.

For those who aren't yet satisfied, you just have to step up and pay for the next more expensive solution and keep spending until you're broke or happy (or both). If you find it, I don't want to come over and hear it, thus spoiling my current stasis.

Well, okay, maybe just to listen once...

What I can afford, when I can afford it...
filecat13 is offline  
post #309 of 394 Old 10-12-2009, 04:00 PM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by rabident View Post

DynamicEQ is interesting. Not so much for what it does, but what it means. Remember all those people complaining of lean bass? It turns out the well known characteristic of human hearing where bass needs to be louder at lower listening levels to be perceived the same as it is at reference wasn't included as part of the original Audyssey correction algorithm. DynamicEQ fixes that.

A whole group of naysayers were outright dismissed as bass heads that didn't like reference sound, but the introduction of DynamicEQ means those same people were actually right. They were hearing flaws in Audyssey's implementation (below reference level).

I used to wonder why a some audiophiles that did use equalization preferred a house curve that wasn't flat, but rather boosted at both ends of the frequency spectrum, the so-called smiley curve. Then it occured to me that, via trial and error, they were implementing a crude static version of Dynamic EQ when listening at levels lower than the mixing environment. In other words, the house curve was approximately perceptually flat when hearing's decreased sensitivity to lows and highs are compensated for via equalization.

The issue of equalizing to a mostly flat target curve (with or without a slight roll-off), but listening at levels different from the mixing levels, is not a flaw only in Audyssey correction, it is a flaw in virtually all equalization methods. Audyssey I believe is unique in that it boosts bass, highs and surround levels to compensate for loss in sensitivity at lower listening levels. Further, it does it dynamically by monitoring in real-time the actual levels of the content adjusting for the quieter passages, something that conventional equalization simply can not do.

Quote:


Is it possible something similar is happening with 2 channel? Could some of the "one size fits all" improvements tailored towards multichannel do more harm than good when applied to 2 channel?

For example maybe 2ch sounds better with Audyssey off because their algorithm reels in the decay time. With multichannel, the reverb is captured in the surround channels so removing decay improves clarity. With 2ch reducing the decay by the same amount may be perceived as sucking the life out the presentation making it sound overly dry & clinical.

I'm inclined to believe Kal's previous explanation:

Quote:
Originally Posted by Kal Rubinson View Post

I know this will be a "hot button" for some but many long-term audiophiles have become accustomed to a particular rendition of stereo sources based on years of listening in environments where the room acoustics contribute significantly to the overall soundstage and imaging (to say nothing of FR). Indeed, successful stereo often relies more heavily on the room's contribution even though it may be spurious in many ways.

As I mentioned earlier, if a room is acoustically designed for listening to multichannel content and two-channel content is played, it will sound dry, but that is not the fault of equalization, that is the fault of playing the wrong content in the wrong room.

Quote:


Or it could be different mixing standards. I find it ironic that Audyssey's "Reference" curve isn't flat. Reference sound is thrown around like it's an industry standard, but it's just Audyssey's proprietary curve they think makes all your music and movies sound "best". You don't like the high frequency content removed from your CD's... well you just don't like reference sound, son.

With regard to why Audyssey has a target curve that rolls off, it is because their research shows that the majority of home listening environments is in the reverberant field not the near field. Therefore, for film standards , the roll-off is needed to tame brightness caused by the differences between the recording and listening acoustic environments. For folks who are seated in the near field at home, the Flat target curve may be more appropriate. However, a great deal of music is mixed much hotter than film standard reference, so we may find that regardless of whether we are seated in the near field, gentle high frequency roll-offs may still be needed to listen at moderate levels at home in a typically small room without fatigue.

Audyssey makes no claim that for CDs, mixed to no specific standard, that Dynamic EQ will make them sound better. It may or it may not. Its not that Audyssey claims the customer doesn't like reference, there is no reference for Dynamic EQ to adhere to for music. If it sounds bad, they advise to turn off Dynamic EQ. Some new models permit different levels of Dynamic EQ to compensate for music mixes that are hotter than film standards. Another workaround for devices that don't permit adjustments is to decrease the input source levels. This cause the user to manually turn up the master volume to get to the same comfortable listening level, which in turn causes Dynamic EQ to reduce its corrections thinking it is closer to reference.

Quote:


My impression of the Pro pack is it helps bring Audyssey back in line as a tool instead of magic bullet.

Yes, for example, each room and primary listening location within the room, is likely to need a different amount of roll-off, than the standard Audyssey Reference curve, that is, if it needs a roll-off at all. So the Pro software offers a bit more adjustability to more closely tailor the roll-off to the particular acoustic environment.

Larry
LarryChanin is offline  
post #310 of 394 Old 10-12-2009, 04:29 PM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by audioguy View Post

Audyssey will tell you there is NO two channel reference. There are a set of standards for movies that the director may or may not follow and it is that standard to which Audyssey strives.

Having installed hundreds of two channel digital room correction systems (not Audyssey), in 99% of the cases, there was no harm done. In a very few of the cases the improvement may or may not have justified the expense but in every other case, there were major improvements. And the listening environments were from very high end speakers in family rooms (no treatment) to dedicated listening rooms with appropriate treatment.

In virtually all of these cases, the digital signal from the CD transport went to the correction system and then was converted to analog either by our product or an external DAC.

Audyssey or even Audyssey Pro will work perfectly fine for most (and that is a key word) environments but in those cases where it does not work well, there may not be enough flexibility even in Audyssey Pro to make it work. And I can assure you that the flexibility required to adapt the product to those more complex room situations implies product complexity and most folks don't really have the acoustic (or mathematical) knowledge to properly use such a system.

As I have stated previously, there are more flexible products on the market that cost 10 times more.

As to what an appropriate target curve might be, there are a couple of approaches. The one we used that provided the best results was to design a curve that had the general shape of the FR at the listening position without correction --- and with the knowledge (from manufacturers spec) of what the low end extension was.Audyssey determines low end cut off based upon the 3db down spot which, in some cases is NOT the correct low end extension point if there happens to be an anomolie in the room that could create that size null. As an example, all Dunlavy speakers have about a 4db roll-off from 10K to 20K at the listening position (not in an anechoic chamber) and we built that roll-off into our target curve. When we used a flat target curve, the sound would become fatiguing with some material.

Audyssey for the price and functionality is a no brainer. If it doesn't work in your environment, there are other much more expensive solutions.

Hi,

You make a lot of excellent points.

I have skimmed over some Audyssey Pro literature and it appears they offer a limited number of target curves and they can only be adjusted by +/- 3 dB.

Yes, Audyssey admits that theoretically if a modal peak has the right characteristics it might fool MultEQ into calculating an erroneous -3 dB point, but this is a rare occassion.

Just one point, in the current devices Audyssey offers a suite of software, MultEQ in its various forms, including the Pro version, Dynamic EQ and Dynamic Volume. Many folks feel that Dynamic EQ/Volume is as important to their enjoyment as MultEQ. So even if another equalization approach is more flexible, it will not offer features that dynamically adjusts the equalization to yield a perceptually flat response when listening a levels lower than the mixing environment.

Larry
LarryChanin is offline  
post #311 of 394 Old 10-12-2009, 05:00 PM
AVS Addicted Member
 
Kal Rubinson's Avatar
 
Join Date: Mar 2004
Location: NYC + Connecticut
Posts: 28,525
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 132 Post(s)
Liked: 163
Quote:
Originally Posted by LarryChanin View Post

...and they can only be adjusted by +/- 3 dB.

That's not really true. According to the manual (pages 31-32), once cannot set a point that is more than +/- 3dB from 0dB but, as in the example shown, one can move a point on one of the set curves that is outside that window to any point within the window.

Kal Rubinson

"Music in the Round"
Senior Contributing Editor, Stereophile
http://www.stereophile.com/category/music-round

Kal Rubinson is online now  
post #312 of 394 Old 10-12-2009, 08:19 PM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Kal Rubinson View Post

That's not really true. According to the manual (pages 31-32), once cannot set a point that is more than +/- 3dB from 0dB but, as in the example shown, one can move a point on one of the set curves that is outside that window to any point within the window.

Hi Kal,

Thanks for taking the time to explain this to me in the Audyssey thread.

However, I suspect some of the professionals here may disagree that being limited to +/- 3 dB on the entire Flat target curve and to +/- 3 dB in the portion below ~12 kHz on the Reference target curve offers enough flexibility for them.

Thanks again for the clarification.

Larry
LarryChanin is offline  
post #313 of 394 Old 10-12-2009, 08:26 PM
AVS Addicted Member
 
Kal Rubinson's Avatar
 
Join Date: Mar 2004
Location: NYC + Connecticut
Posts: 28,525
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 132 Post(s)
Liked: 163
Quote:
Originally Posted by LarryChanin View Post

Hi Kal,

Thanks for taking the time to explain this to me in the Audyssey thread.

However, I suspect some of the professionals here may disagree that being limited to +/- 3 dB on the entire Flat target curve and to +/- 3 dB in the portion below ~12 kHz on the Reference target curve offers enough flexibility for them.

Thanks again for the clarification.

Larry

Mebbe. However, this is not a correction curve but a target and I have no situations in which I would need more than that 6dB range.

Kal Rubinson

"Music in the Round"
Senior Contributing Editor, Stereophile
http://www.stereophile.com/category/music-round

Kal Rubinson is online now  
post #314 of 394 Old 10-13-2009, 12:27 AM
AVS Special Member
 
hifisponge's Avatar
 
Join Date: Jan 2004
Location: Redmond, WA
Posts: 7,516
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
BTW - Do any of you Audyssey Pro users know what the vertical scale is in the graphs below?



Is it 3 or 5dB between each horizontal line?
hifisponge is offline  
post #315 of 394 Old 10-13-2009, 02:42 AM
AVS Club Gold
 
SierraMikeBravo's Avatar
 
Join Date: Mar 2007
Location: Topeka, KS
Posts: 1,618
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 90 Post(s)
Liked: 65
Quote:
Originally Posted by Kal Rubinson View Post

Thanks for taking the bait.

What bait???? You have to remember Kal that speakers are generally flat in the near-field with jut a slight boost in the higher frequencies. So, wouldn't you naturally be able to recreate the mixed recording just as the engineer intended it (not necessarily the actual recording) provided you removed the effects of the room? What are you then left with? I can see this is going nowhere really fast.

Shawn Byrne
Erskine Group
CEDIA Certified Professional EST II - HAA Level III Certified -THX Certified Professional

Design-Video & Audio Calibration Information

The original Pro Theater Layout
SierraMikeBravo is offline  
post #316 of 394 Old 10-13-2009, 05:27 AM
AVS Special Member
 
rabident's Avatar
 
Join Date: Mar 2000
Posts: 2,056
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 49 Post(s)
Liked: 27
Quote:
Originally Posted by noah katz View Post

That doesn't wash - there was no DynamicEQ before they used Audyssey, nor does it seem to be a complaint w/other EQ systems.

Other EQs have enough flexibility to deal with the problem, at least for a target volume level. If listening less than reference level, bass can be manually boosted to compensate.

Gen 1 Audyssey came later, initially to most users as a closed, proprietary, all or nothing option. Calibration was done to reference levels and didn't allow any further tweaking. Users coming from other EQ's with manually applied low frequency compensation experienced bass suck-out with Audyssey.

Gen 2 Audyssey's introduction of DynEQ acknowledges the problem and provides a solution.

 

 

rabident is offline  
post #317 of 394 Old 10-13-2009, 06:42 AM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by rabident View Post

Other EQs have enough flexibility to deal with the problem, at least for a target volume level. If listening less than reference level, bass can be manually boosted to compensate.

Hi,

Yes, there is an issue, but as I mentioned earlier, the problem associated with listening below reference levels is not strictly an Audyssey problem.

When listening at below reference level yes, hearing is less sensitive to bass, but it is also less sensitive to treble and to sounds coming from the rear. Furthermore, the levels of recordings do not stay at the same volume throughout, they can vary greatly. Other EQs that allow the user to manually boost the bass (or the treble) by a fixed amount, are incomplete static solutions that do not provide a perceptually flat response as the content's levels change, nor do they dynamically adjust the levels of sounds coming from the rear.

Larry
LarryChanin is offline  
post #318 of 394 Old 10-13-2009, 09:33 AM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by SierraMikeBravo View Post

Audyssey also corrects above the transition frequency (all those hundreds of little corrections throughout the frequency response spectrum). The only reason to do this, other than a bad speaker, is for timbre matching and dealing with boundary issues. I am not saying this is a bad thing, but when calibrating manually, I generally leave everything above the transition frequency alone, meaning I don't use equalization on anything but the sub(s) and deal with SBIR issues through positioning and treatment unless there are issues with the FR above it or for a few other perhaps preferable aspects.

Hi Shawn,

On the advisability of equalizing above the transition frequency I doubt we'll ever reach a consensus, but I think its healthy to exchange differing views.

Here are some remarks by Audyssey on the subject.

"Official" Audyssey thread, posting #19358.

"Official" Audyssey thread, posting #19469.

"Official" Audyssey thread, posting #19480.

"Official" Audyssey thread, posting #19536.

Larry
LarryChanin is offline  
post #319 of 394 Old 10-13-2009, 09:54 AM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by amirm View Post

How come? I find my TacT to do an incredible job on both stereo and 5.1. Indeed the effect for stereo is even stronger.

Hi Amir,

I'm not familar with the TacT.

Does it equalize above the transition frequency?

I would value your opinion on the pros and cons of equalizing above the transition frequency with these sophisticated software approaches in contrast to manual parametric equalization.

Thanks.

Larry
LarryChanin is offline  
post #320 of 394 Old 10-13-2009, 10:44 AM
AVS Special Member
 
audioguy's Avatar
 
Join Date: Jun 2001
Location: Not far from Atlanta - but far enough!
Posts: 3,596
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 473 Post(s)
Liked: 336
Quote:
Originally Posted by hifisponge View Post

BTW - Do any of you Audyssey Pro users know what the vertical scale is in the graphs below?

Is it 3 or 5dB between each horizontal line?

I had the same question and asked Audyssey. The answer is none of the above. The graphs are only a general indication of the before and after and not detailed and specific plots. That said, they are still informative.

New Theater

Don't count the years. Make the years count. Lou Holtz
audioguy is online now  
post #321 of 394 Old 10-13-2009, 10:53 AM
RUR
Innocent Bystander
 
RUR's Avatar
 
Join Date: Feb 2007
Location: California Republic
Posts: 2,389
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 145 Post(s)
Liked: 77
Quote:
Originally Posted by LarryChanin View Post

Does it equalize above the transition frequency?

I would value your opinion on the pros and cons of equalizing above the transition frequency with these sophisticated software approaches in contrast to manual parametric equalization.

TacT provides full-frequency equalization, though the user can choose to equalize only frequencies below any chosen frequency. It equalizes to a flat FR, but has 12 user-selectable "house" curves, as well as the ability to tweak these curves to suit individual preference.

In my case, I'm using a 2ch-only version in a dedicated stereo setup so I can't comment on 5.1. I gave up a fairly high-end analog preamp for the TacT, and I've been extremely impressed with the results.

Edited: User can choose to EQ only frequencies below a chosen point, but may not choose to EQ only frequenceis above a chosen point.
RUR is offline  
post #322 of 394 Old 10-13-2009, 10:56 AM
AVS Special Member
 
audioguy's Avatar
 
Join Date: Jun 2001
Location: Not far from Atlanta - but far enough!
Posts: 3,596
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 473 Post(s)
Liked: 336
Quote:
Originally Posted by LarryChanin View Post

Hi Amir,

I'm not familar with the TacT.

Does it equalize above the transition frequency?

I would value your opinion on the pros and cons of equalizing above the transition frequency with these sophisticated software approaches in contrast to manual parametric equalization.

Thanks.

Larry

There are two Tact product types. The 2.0 is a two channel (no sub) digital room correction product (which is what I own) that operates in the time domain. Their other room correction products (2 channel and 10 channel) fix (it is NOT frequency based EQ) above the transition point. They all use time analysis (at 1 or more measuring spots) and you can set crossover, slope, etc and they will time align the subs to the mains.

It has a LOT of flexibility as it should given it (the two channel version with sub support) costs almost 10 times the cost of Audyssey Pro. A user must have some reasonable knowledge of room acoustics so as not to blow up drivers, burn crossover, etc (I have done both when I first learned to us it).

It is for that reason that the Audyssey Pro solution is so wonderful for the masses as it may be impossible to actually "break" anything and, for most people, get great results.

New Theater

Don't count the years. Make the years count. Lou Holtz
audioguy is online now  
post #323 of 394 Old 10-13-2009, 11:00 AM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by RUR View Post

TacT provides full-frequency equalization, though the user can choose to equalize only frequencies above or below any chosen frequency. It equalizes to a flat FR, but has 12 user-selectable "house" curves, as well as the ability to tweak these curves to suit individual preference.

In my case, I'm using a 2ch-only version in a dedicated stereo setup so I can't comment on 5.1. I gave up a fairly high-end analog preamp for the TacT, and I've been extremely impressed with the results.

Hi,

Thanks for the response.

So you equalize the full frequency range and are impressed with the results?

Larry
LarryChanin is offline  
post #324 of 394 Old 10-13-2009, 11:06 AM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by audioguy View Post

There are two Tact product types. The 2.0 is a two channel (no sub) digital room correction product (which is what I own) that operates in the time domain. Their other room correction products (2 channel and 10 channel) fix (it is NOT frequency based EQ) above the transition point. They all use time analysis (at 1 or more measuring spots) and you can set crossover, slope, etc and they will time align the subs to the mains.

Hi,

To clarify, your version doesn't equalize above the transition frequency?

Thanks.

Larry
LarryChanin is offline  
post #325 of 394 Old 10-13-2009, 11:32 AM
AVS Addicted Member
 
Kal Rubinson's Avatar
 
Join Date: Mar 2004
Location: NYC + Connecticut
Posts: 28,525
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 132 Post(s)
Liked: 163
Quote:
Originally Posted by SierraMikeBravo View Post

What bait????

Just keeeding.

Quote:


You have to remember Kal that speakers are generally flat in the near-field with jut a slight boost in the higher frequencies. So, wouldn't you naturally be able to recreate the mixed recording just as the engineer intended it (not necessarily the actual recording) provided you removed the effects of the room? What are you then left with? I can see this is going nowhere really fast.

Depends on how you are using the term near-field. As used for listening, it is within the point where room effects begin to dominate. That does not mean that they are not affecting the sound or the measurements. For measurement, it is so close that room effects are not significant. However, the speaker was likely not designed to be listened to at that distance. So, I agree that this is going nowhere and that was my intent. There is no way to use these arguments to justify abjuring EQ.

Kal Rubinson

"Music in the Round"
Senior Contributing Editor, Stereophile
http://www.stereophile.com/category/music-round

Kal Rubinson is online now  
post #326 of 394 Old 10-13-2009, 11:34 AM
RUR
Innocent Bystander
 
RUR's Avatar
 
Join Date: Feb 2007
Location: California Republic
Posts: 2,389
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 145 Post(s)
Liked: 77
Quote:
Originally Posted by LarryChanin View Post

Hi,

Thanks for the response.

So you equalize the full frequency range and are impressed with the results?

Larry

Yes I EQ the full FR using their 2.2XP "Stereo Processor"/preamp. So impressed I don't think I can go back to a non-EQ product. For completeness sake, I have a dedicated 2ch room which is fairly well treated with conventional absorbtion/diffusion products.
RUR is offline  
post #327 of 394 Old 10-13-2009, 04:12 PM
AVS Special Member
 
audioguy's Avatar
 
Join Date: Jun 2001
Location: Not far from Atlanta - but far enough!
Posts: 3,596
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 473 Post(s)
Liked: 336
Quote:
Originally Posted by LarryChanin View Post

Hi,

To clarify, your version doesn't equalize above the transition frequency?

Thanks.

Larry

There is no "transition point" for my product. Mine is the 2.0. So I correct full spectrum. The 2.2 which allows for correction of a separate sub(s) is what you are referring two and if I were to ever switch to a sub supported two channel system, that is what I would purchase. (I will not use Audyssey for two channel as the analog section of my pre-pro is not good enough for my listening requirements and Audyssey Pro does not let me do some things that I believe are mandatory for a true high-end two channel listening environment.)

Let me tell you about a huge potential advantage of correcting the entire frequency spectrum in a two channel environment. We all know about fixing bass problem caused by room boundaries but even in a perfectly symmetrical room, the chance of the left and right impulse response (and hence FR) being identical are pretty slim (in my experience of doing hundreds of rooms --very close to ZERO). To the degree the difference increase, the benefits of correction in the mids and highs increases. What you will get with room correction done correctly is (among other things) increased image focus and stability. Assume the uncorrected room response at, say 2K is +1.5 db on the left channel and -3 db on the right channel (not at all unusual). As musical content containing that frequency plays, the image will gravitate between left and right (maybe very slightly but clearly perceptible) and hence cause image shift. By correcting that FR deviation, the image becomes more stable. Trust me that this is not theoretical but does, in fact, occur. (Maybe the selection of 2K is not accurate but the point remains). Obviously in a multichannel system, this specific benefit somewhat is reduced but not completely.

I have been in a few rooms where room correction above the bass (and in one example including the bass) did absolutely nothing. But that is the exception.

New Theater

Don't count the years. Make the years count. Lou Holtz
audioguy is online now  
post #328 of 394 Old 10-13-2009, 06:52 PM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by audioguy View Post

There is no "transition point" for my product.

Hi,

Thanks for your very informative response.

With regard to the transition frequency, I was referring to the Schroeder Transition frequency for your room.

f = 2000*(sqrt T/V)

Where T is the reverberation time in seconds, and V is the room volume in cubic meters.

As I understand it, below the transition frequency acoustics are dominated by relatively isolated, orderly room modes while above the frequency acoustics are dominated by complex overlapping room modes and reflections.

I don't have a good grasp of the details, but apparently the controversy about the suitability of equalization above the transition frequency seems to hinge on the fact that wave acoustics (standing wave models) used to predict and correct modal responses at low frequencies doesn't work at high frequencies where the modes are not isolated. So another approach to room correction is needed in place of conventional equalization.

Quote:
Obviously in a multichannel system, this specific benefit somewhat is reduced but not completely.

Perhaps its not so obvious to me.

I would think that in a multichannel system there would be a much greater likelihood that the timbre of the rear speaker array differed from the front speaker array. Much more so than any difference likely to exist between "identical" paired two-channel mains. Therefore, equalization that matches the timbre of multichannel systems, front to back might be extremely beneficial. The only offsetting factor would be that our forward facing hearing sensitivity is greater than our rear, so we are more likely to hear timbre mismatches up front.

Larry
LarryChanin is offline  
post #329 of 394 Old 10-13-2009, 09:06 PM
Advanced Member
 
vantagesc's Avatar
 
Join Date: Apr 2007
Location: Los Angeles
Posts: 822
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 37
Quote:
Originally Posted by hifisponge View Post

BTW - Do any of you Audyssey Pro users know what the vertical scale is in the graphs below?

Sorry if I missed it, but what is that notch in upper midrange / lower treble that appears in the post-Audyssey charts? Is that a BBC dip?
vantagesc is offline  
post #330 of 394 Old 10-14-2009, 05:39 AM
AVS Special Member
 
LarryChanin's Avatar
 
Join Date: Nov 1999
Location: Sarasota, Florida
Posts: 6,810
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by vantagesc View Post

Sorry if I missed it, but what is that notch in upper midrange / lower treble that appears in the post-Audyssey charts? Is that a BBC dip?

Hi,

Here's an excerpt from some Audyssey Pro documentation.

Quote:


It is recommended that you engage the Midrange Compensation option for your first listening test (this is selected by default). Midrange compensation is sometimes necessary to correct for the directivity differences that often occur in that frequency range due to the crossover circuitry or horn-loaded speakers. You can later return to this screen and disengage this option if you prefer.

Larry
LarryChanin is offline  
Reply Ultra Hi-End HT Gear ($20,000+)

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off