Audyssey this and Audyssey that

[Roc Rinaldi]

What do you know and how do you feel about Audyssey room compensation?

What does it do? Does it work? How well does it work?

[Groomlakearea51]

Re: AVR-2807's.... It's a room equalization curve "mode" that, in theory, should compensate after the microphone setup. For a conventional system it works quite well. My only problem with it is that the AVR is designed for HT, not multiple "stereo" speakers (A+B+C+D, etc.). It's designed for front, (single) center, surrounds, rears and a sub.

I read the manual - about 10 times (Manual? It's a crew served weapon, needs wheels, and a Master's degree in brain surgery to figure it out...), but finally did "easy setup" in the "wall of voodoo" room with the microphone thing for the hell of it.... It determined that my Klipschorns are small, my Heresy's are big, etc. Sounded like I was in a submarine with the speakers at the forward torpedo room and I was in the reactor space.... Oh well, I figured I gotta' be smarter than the tools I work with...

That being said, I then "reset" that amp to default factory (the "before you screw around with it" settings) and went through the manual in the "advanced" part (Part 4, Section 8, subsection 22, page 934... just kidding[6] - it was on page 60...) and set all of the speakers as "large", then selected "Audyssey", and it works fairly well, provided the speakers are where they are supposed to be. But alas, they are not... So as far as the "wall of voodoo" room... I just use 7 channel stereo mode, or "direct" (Cornwalls & LaScalas). I am, however, going to have to switch which speakers are identified as which to the amp to make that work really well. I really want the Klipschorns to be Front-A and the Cornwalls as Front-B, and the LaScala's (connected in series to appear as a 16 ohm speaker) as the "center". I can "scatter" Heresy's in that room to simulate surrounds and rears. Certainly don't need a sub in there....

That being said, the second 2807 unit works very well in the living room with nothing but Heresy's scattered about in the proper "HT" configuration and a KSW-12 subwoofer. That's the key. You really have to have the HT speakers where they are supposed to be for the Audyssey room correction mode to work properly. Key thing here at my end is the WAF.... My wife comes home, uses a remote to turn it on and watches the Gilmore Girls, and she's happy. Before it was turning on three amps, master source switching system, mixer with master volume, setting amp volumes, etc., etc. and every time she changed the channel on DTV, she had to get up and adjust the volume. So.... it was an easy choice!!! Sold the old integrated monsters from the living room, and the remaining 2 or 3 are going into the dedicated Klipschorn "man cave" when it's completed.... With appropriate and due credit to Mel Brooks' Blazing Saddles, "We don't need no stinkin surround sound".....

[DrWho]

short answer: room acoustics issues can only be fixed by fixing the

acoustics of the room. Trying to compensate with EQ is at best a

band-aid. The wow-factor might make it seem like things are better at

first, but the room acoustics aren't changed in the process and

eventually you'll realize that you've just shifted the distortion

signature and haven't accomplished anything. It's definitely one of

those things where different is perceived as better.

That's not to say that there can't be any true benefit to implementing

these EQ devices, but it would be the absolute last thing I would

recommend. There are many more options out there (some of which even

cost less) that will sound infinitely better.

I hope you don't mind the overly opinionated response. The concept of

EQ'ing a room was given up in the professional industry back in the

80's once everyone realized it doesn't work. Further development in

measurement techniques has revealed the reasons why the EQ doesn't

work...which involves looking at the time domain, not the typical

frequency response perspectives.

Though I must confess that it would be extremely awesome if these devices worked...

[Groomlakearea51]

Dr Who is absolutely right; It's best to attack the problem before using the EQ systems supplied. But.... if one is stuck with a particular room design and the "listening mode" (read that as the wife and kids watching DTV or movies), it's handy to have. In my case, the living room, based on the design of the house, is about as "acoustically hopeless" as you can get. Vaulted ceiling at 14' dividing a 30' x 30 room with a 8' height false wall running through the middle (big horizontal hole running down the middle...), huge fireplace structure dead in the middle of the false wall, kitchen/ dining on one side, and no "Klipschorn" corners in the other side (living room) part at all? No wonder I just use Heresy's and the AVR system in that room. Now.... as the construction of the "stereo/ office" room proceeds..., the bass traps, diffusion & absorption points, and other "treatments" becomes part of the process. Everything, however, is a compromise of some sort or to some degree.

Note for the Doctor: Wanna' take a look at the Denon "FAQ" literature on the Audyssey system below and see if they are getting any better at this ? Interestingly, they clearly state/admit there is no substitute for room treatment.

"There are two fundamental differences from every other Room Eq method available in AV receivers today. The first is that Audyssey MultEQxt is not based on parametric equalization. Parametric equalization relies on a few bands that are centered at certain frequencies. These bands do not provide sufficient resolution to address many room acoustical problems. Also, parametric bands tend to interact so that changes at one frequency have undesirable results at nearby frequencies. Moreover, parametric equalization methods use a particular type of digital filter called Infinite Impulse Response (IIR) that only attempts to correct the magnitude response in the frequency domain. These filters can cause unwanted effects, such as ringing or smearing, in the time domain particularly as the bands get narrower. MultEQxt uses Finite Impulse Response (FIR) filters for equalization that use sevral hundred coefficients to achieve much higher resolution in the frequency domain than parametric bands. Furthermore, by their nature, FIR filters simulatneously provide correction in the frequency and time domains.

The second major difference is that MultEQxt combines multiple measurements to create equalization filters that better represent the acoustical problems in the room. Most other methods only perform a single point measurement and this can result in making other locations in the room sound worse than before equalization. There are some methods that use spatial averaging to combine multiple room measurements. Although this is a step above single-point correction, it does not always provide optimum correction. For example, it is common to find a peak at a certain frequency in one location and a dip at the same frequency at another nearby location. The averaging methods will add the peak and the dip and this will result in an apparent flat response at that frequency, thus causing the equalization filter to take no action. MultEQxt uses a clustering method to combine measurements so that acoustical problems are better represented, thus allowing the equalization filter to perform the appropriate correction at each location.

Once the room measurements are completed, MultEQxt calculates a filter for each loudspeaker channel including the subwoofer. The role of these filters is to achieve a particular frequency response within the entire listening area for each loudspeaker. This curve is determined based on several acoustical and program materiial considerations and is called a target or calibration curve.

Contrary to popular belief, a target curve that is flat from 20 Hz to 20 kHz is not always the one that will produce the correct sound. There are several reasons for this including the fact that loudspeakers are much more directional at high frequencies than they are at low frequencies. This means that the balance of direct and room sound is very different at the high and low ends of the frequency spectrum.

The Audyssey target curve setting makes the appropriate correction at high frequencies to alleviate this problem. A slight roll-off is introduced that restores the balance between direct and reflected sound. The Flat setting uses the MultEQxt filters in the same way as the Audyssey curve, but it does not apply a high frequency roll-off. This setting is appropriate for very small or highly treated rooms in which the listener is seated quite close to the loudspeakers. It is also recommended for all rooms when the receiver is in THX processing mode. This allows THX re-equalization to operate exactly as it was intended.

There is a belief that room correction should only be applied to frequencies below 300 Hz or so because that is the frequency range in which most of the room problems occur. This belief is based on an inherent assumption that a properly designed loudspeaker will perform as desired at higher frequencies and thus require no correction. This is not at all contradictory to MultEQxt. If the loudspeaker is in fact properlly designed then no correction will be applied to it. One simple fact that the proponents of this theory seem to overlook is that even the best designed loudspeakers will suffer from artifacts at high frequencies produced by reflections from nearby flat surfaces such as plasma screens or cabinets. MultEQxt performs this kind of correction when it is needed to allow the loudspeaker to achieve the performance it was designed to have.

MultEQxt detects absolute phase for each loudspeaker. Some loudspeakers are designed with intentional phase reversals in the drivers in order to address crossover problems. MultEQxt will detect that and report an error. The best course of action is to simply check the wiring and press Skip if it is correct. MultEQxt simply reports a possible wiring reversal, it does not automatically switch the phase.

Many powered subwoofers do not provide the capability to defeat the built-in low-pass filter. These filters, by their nature, introduce additional delay in the signal and MultEQxt finds that and reports it. The optimum solution is to turn the filters off (often called LFE mode in subwoofers). If that is not possible, set the low pass frequency to the highest possible setting and leave the distance reported as it. MultEQxt will compensate for the added delay and time align the subwoofer to the satellite channels so that the optimum blend is achieved.

The equalization performance increases with the number of measurements. Audyssey recommends a minimum of 4 with most rooms performing best with 6 measurements. The maximum number of measurements is limited by the available memory in the receiver or controller and in some products can go up to 8. Depending on the model of Denon A/V receiver, the number of points that can be measured is the only difference in the MultEQxt system. The ideal calibration consists of 68 measurements that encompass the listening area. It is important to have the microphone in the main listening position for the first measurement so that the delays are calculated correctly. After that, the mic should be moved around so that it covers an area within which listeners will be seated.

The Denon microphone is calibrated to a ¼ industry-standard measurement microphone. The correction is applied to the measurements as they are being taken. It is important to use ONLY the microphone that comes with the Denon A/V receiver, as the calibration curve built-in to the receiver is specific to that microphone.

Does MultEQxt eliminate the need for acoustic treatment? No. Although MultEQxt will improve sound significantly in untreated rooms, a properly treated room calibrated with MultEQxt can achieve stunning results throughout the listening area. This is one of the unique strengths of MultEQxt. Room correction methods based on parametric equalization do not have enough bands or processing power to apply correction in the bass frequency range. MultEQxt uses a unique implementation of FIR filters that achieves very good resolution at frequencies below those that standard FIR filters can reach. The resolution of the MultEQxt filters varies with frequency and this allocates more of the filter correction power where it is needed the most: in the lower frequencies.

[Roc Rinaldi]

short answer: room acoustics issues can only be fixed by fixing the acoustics of the room. Trying to compensate with EQ is at best a band-aid. The wow-factor might make it seem like things are better at first, but the room acoustics aren't changed in the process and eventually you'll realize that you've just shifted the distortion signature and haven't accomplished anything. It's definitely one of those things where different is perceived as better.

That's not to say that there can't be any true benefit to implementing these EQ devices, but it would be the absolute last thing I would recommend. There are many more options out there (some of which even cost less) that will sound infinitely better.

I hope you don't mind the overly opinionated response. The concept of EQ'ing a room was given up in the professional industry back in the 80's once everyone realized it doesn't work. Further development in measurement techniques has revealed the reasons why the EQ doesn't work...which involves looking at the time domain, not the typical frequency response perspectives.

Though I must confess that it would be extremely awesome if these devices worked...

Dr. Who, I must say that you do know your stuff.

[Roc Rinaldi]

Dr. Who & area-51,

I am seriously considering the purchase of the Audyssey Sound Equalizer. I have carefully read your comments and suggestions. Thank you for offering your thoughts and opinions.

Would you recommend that I buy it or not?

My listening room is in pretty good shape. It's a large room (23 x 22 x 7.3) with lots of sound deadening. The room is on the dead side and doesn't seem to have many reflections nor echos. I'm pretty happy with the sound as it is right now, but I still believe that I can improve it significantly. The room does have its places where the bass is louder and other places where the bass seems to disappear. Perhaps the Audyssey Sound Equalizer could further even out the sound for more than one spot in the room. I need about three seating locations to sound really good.

Do you happen to know how much the Audyssey Sound Equalizer costs?

[Groomlakearea51]

Would you recommend that I buy it or not?; Do you happen to know how much the Audyssey Sound Equalizer costs?

Buy vs not buy? Depends on how you will use it, I suppose. According to Audyssey, you have to go through one of their "installers" or become an "installer" to buy the unit. http://www.audyssey.com/soundequalizer.html If I were to "buy it" again, I would still obtain it allready "built in" a new AVR.

Quoting Audyssey:

"To become a registered Audyssey Installer contact your local Audyssey Manufacturer's representative or contact us at installer@audyssey.com. If you are a customer who wishes to buy the Audyssey Sound Equalizer and want to locate a registered Audyssey Installer in your area, please contact us at installer@audyssey.com. "

On the other hand, a number of AVR's have the system installed under license; http://www.audyssey.com/index.html Look at the lower right side of the home page.

I cannot find any reference to a suggested MSRP; I would suspect that they will only sell through a retailer/ installer. It's likely that the unit costs several hundred dollars, maybe more.

Hope that helps.

[mas]

Marshall, having read that, and their web site several times (my brain hurts!!!), they use so many big words without saying much of anything.

First, they spend allot of time talking about "that Audyssey MultEQxt is not based on parametric equalization". MultEQxt uses Finite Impulse Response (FIR) filters for
equalization that use several hundred coefficients to achieve much
higher resolution in the frequency domain than parametric bands.
Furthermore, by their nature, FIR filters simultaneously provide
correction in the frequency and time domains."

"For example, it is common to find a peak at a certain frequency in
one location and a dip at the same frequency at another nearby
location. The averaging methods will add the peak and the dip and this
will result in an apparent flat response at that frequency, thus
causing the equalization filter to take no action. MultEQxt uses a
clustering method to combine measurements so that acoustical problems
are better represented, thus allowing the equalization filter to
perform the appropriate correction at each location."

They don't "average", they "cluster". This is a highly advanced technique that , along with SIM, is widely used in another activity which I suspect Amy will object to my mentioning even more than an allusion to drummer jokes!

"Contrary to popular belief, a target curve that is flat from 20 Hz
to 20 kHz is not always the one that will produce the correct sound.
There are several reasons for this including the fact that loudspeakers
are much more directional at high frequencies than they are at low
frequencies. This means that the balance of direct and room sound is
very different at the high and low ends of the frequency spectrum."

Let's cut to the chase. At the risk of offending the audiophiles, we don't care about a flat frequency response here. We are dealing with our speakers as the source - whatever their crazy response characteristics are. So the direct sound is as it is. You can EQ that. And a parametric EQ is great for that application. But that has NOTHING to do with room correction! Thus far the entire discussion has been non sequitur to the issue of speaker-room interaction.

You have the direct signal from the speaker, with whatever its frequency response may be. Fundamentally, thats an issue between you and your speaker manufacturer. Now ALL resultant variances from this within the room is a result of superposition - the combination of the direct signal with the many reflected signals that recombine with each other at any particular point in space in the room. Now ALL EQ can do is to change the character of the direct signal, it cannot change the fundamental nature of the resulting superposition in the room. And let me clarify this; such action may result in a different sound, but it will not in any way address the issue of superposition and the effects that result from superposition. To make this even simpler...I can change the frequency response of the direct signal by putting on a different CD or record! There, I have effectively EQ'd the direct sound radically. But I have done NOTHING to change the nature of the interaction between the direct signal and the reflected signals via the phenomena called superposition that results in comb filtering and polar anomalies.

But I could spend lots of time discussing the nature of FIR versus IIR filters and all sorts of neat stuff! Are you impressed or sufficiently baffled yet?

"There is a belief that room correction should only be applied to
frequencies below 300 Hz or so because that is the frequency range in
which most of the room problems occur. This belief is based on an
inherent assumption that a properly designed loudspeaker will perform
as desired at higher frequencies and thus require no correction. This
is not at all contradictory to MultEQxt."

That is one belief, albeit akin to the belief that the world is flat. Both are equally nonsense. But it tells us exactly where they are going! They have effectively declared speaker-room interaction above 300 Hz moot and unimportant. And not only is that "not at all contradictory to MultEQxt" ,it is fundamental to their purpose!

You see, we can debate filter topologies (FIR and IIR) ad nauseum, but when they suddenly say that "room correction should only be applied below 300 Hz" we suddenly realize that all of the talk about the 20-20KHz frequency response is a complete non sequitur! Now they are talking of room modes.

And to a small degree, room modes can be equalized. No, this cannot overcome the basic fundamentals of physics and a tuned space. Nor can it reduce the anomalies anywhere near what tuned traps can do.

And from there on, it claims to attempt to EQ the low frequency response at the listening position. Something any reasonable parametric EQ can do - within the limits possible. And those limits are substantial, as they unfortunately, are unable to overcome the fundamental nature of a tuned pipe.

And that dear friends, is what appropriately applied traps (Helmholtz resonators) and other forms of tuned absorption are for.

Oh, and let me address this as an addendum:

"Does MultEQxt eliminate the need for acoustic treatment? No.
Although MultEQxt will improve sound significantly in untreated rooms,
a properly treated room calibrated with MultEQxt can achieve stunning
results throughout the listening area. This is one of the
unique strengths of MultEQxt. Room correction methods based on
parametric equalization do not have enough bands or processing power to
apply correction in the bass frequency range. MultEQxt uses a unique
implementation of FIR filters that achieves very good resolution at
frequencies below those that standard FIR filters can reach. The
resolution of the MultEQxt filters varies with frequency and this
allocates more of the filter correction power where it is needed the
most: in the lower frequencies."

Too many frequencies? For each of three modes you have a fundamentally resonant frequency and the subsequent harmonics which are multiples of the frequency - 2x, 3x, 4x - up through ~300 Hz. And addressing the fundamental will mitigate the harmonics... Sounds like a crisis indeed!

[Groomlakearea51]

MAS: You too "waded" through Audyssey and Denon... As I said, can't do much with my living room, might as well use the "swiss army knife" that came with the receiver....

Maybe the best way to describe it for Rocrinaldi is one or more of the following:

"If you don't have the money, inclination, or space and room utility considerations to effectively acoustically treat the room, then go for it"? OR

"You are not gaining much with it and would be better off with multiple PEQ's for each speaker pair" OR

"It's essentially a marginal "fix" for room acoustic problems, and if it's included in an otherwise good product, great, can't hurt"

In any event..., what about the Audyssey analysis toolkit itself (forget the EQ - that's tantamount to the plumber telling us we have a leak and he just happens to have the "right part to fix it"..) Or maybe the best question would be: "what's a reasonable cost measuring tool software, pre-amp and mic system that most of us could probably afford?"

[DrWho]

If you wanted to measure stuff for yourself, you could put together

quite a lot of processing power with $150 and a laptop. Or you could

just contact me and I'll rent out my preconfigured measurement rig for

$50 + shipping. And then all you have to do is push a button, send me

the file, and I can help you interpret the results.

[Groomlakearea51]

Dr. Who: That's a great offer for forum members and may be the best solution for Rocrinaldi before he buys an Aydyssey system.

[Roc Rinaldi]

If you wanted to measure stuff for yourself, you could put together quite a lot of processing power with $150 and a laptop. Or you could just contact me and I'll rent out my preconfigured measurement rig for $50 + shipping. And then all you have to do is push a button, send me the file, and I can help you interpret the results.

Dr. Who I have a laptop so can I just rent your equipment and use it to do my measurements?

This thread is related to my other thread entitled "Mis-matching subwoofers" http://forums.klipsch.com/forums/thread/916966.aspx

I would love to just push a button, send you the file, and have you interpret the results.

How do we get started?

[Zen Traveler]

Fwiw, I waded through all of the Audyssey discussions on the AVS Forum and must say there were a ton of opinions I had to consider. I had the Denon AVR 4802R thx ultra II which was damaged (lightening) and received the Denon AVR 4806 thx ultra II in exchange. I must say that Denon's Customer Service is Top Notch once you get over that they don't always answer their phones in a timely manner. [Y]I also can't recommend sending your Denon Products to Pyramid Audio in Austin, Texas to be repaired. [N]

To get back on topic... I have had the unit for 3 weeks and have played around with the Audyssey EQ setup. This thread has some useful information: http://www.avsforum.com/avs-vb/showthread.php?t=795421

I ran the system several different ways after reading the various threads at AVS and decided on 6 positions (capable of 8). It set 6 of my 9 speakers to Large. As posted on that thread, I then went and changed the setting to Small and lfe's upper limit to 120 Hz. I demo'd Top Gun and found that the Flat setting was preferable to the Audyssey setting because it took out some of the brightness of the material on my speakers. When I turned Audyssey off it didn't sound as good (not bad), but I did not go and change the settings like I ran them on my AVR 4802R.

I will run the Audyssey EQ for now because I am satisfied with the results. When the urge hits, I will experiment again with these settings compared to running my HT the way that I did prior (and against consensus by running my speakers as large []).

[mmiles]

Roc (and others),

I heard the MultiEQ almost two years ago at a "Road Show" it was very impressive.

Later that same year at CEDIA I listed again and again. Still very impressive.

Proper room design and acoustical treatments are still the way to go IMHO but this device will enhance even that. Again, IMHO, most multipurpose (media room, home theater and living space) rooms are not properly treated and designed as we know it.

With that said I bought one of the first and have not installed as of yet. It took several months to get it BTW. Lazy I guess...

You will need the "dealer kit" which is the mic, software and weblink (file and print results) that only a dealer has access to., Next you will need to measure at least 4, if not more, listening positions (maybe even the same seat at different ear level heights --- you are a bit taller than Mrs. Roc).

The only down side I see in the unit so far are: no balanced connections (single ended RCA, not a deal breaker however), mic input is on the rear of the unit (the folks at Audyssey say it keeps the front profile clean), PC interface is USB only (LAN would be cool to allow connection with a laptop using a wireless 802 card) again with the jack on the rear of the unit and the cable cannot be left plugged in (but really no need after calibration is done).

At the end of the day the on - off difference was amazing. I forget the movie but it was Kevin Costner and Robert Duval in a cowboy flick and KC was walking in the rain down the center of town. The thunder and rain was awesome sounding. There is one major cool factor I almost forgot. You can push the red button on the panel to listen with the unit on or off. A true guy thing indeed. Trust me you will leave it on!

Regards,

Mike

[Zen Traveler]

...I forget the movie but it was Kevin Costner and Robert Duval in a cowboy flick and KC was walking in the rain down the center of town. The thunder and rain was awesome sounding.

Open Range is the title and I agree, good reference material. [Y]

[Roc Rinaldi]

Roc (and others),

I heard the MultiEQ almost two years ago at a "Road Show" it was very impressive.

Later that same year at CEDIA I listed again and again. Still very impressive.

Proper room design and acoustical treatments are still the way to go IMHO but this device will enhance even that. Again, IMHO, most multipurpose (media room, home theater and living space) rooms are not properly treated and designed as we know it.

With that said I bought one of the first and have not installed as of yet. It took several months to get it BTW. Lazy I guess...

You will need the "dealer kit" which is the mic, software and weblink (file and print results) that only a dealer has access to., Next you will need to measure at least 4, if not more, listening positions (maybe even the same seat at different ear level heights --- you are a bit taller than Mrs. Roc).

The only down side I see in the unit so far are: no balanced connections (single ended RCA, not a deal breaker however), mic input is on the rear of the unit (the folks at Audyssey say it keeps the front profile clean), PC interface is USB only (LAN would be cool to allow connection with a laptop using a wireless 802 card) again with the jack on the rear of the unit and the cable cannot be left plugged in (but really no need after calibration is done).

At the end of the day the on - off difference was amazing. I forget the movie but it was Kevin Costner and Robert Duval in a cowboy flick and KC was walking in the rain down the center of town. The thunder and rain was awesome sounding. There is one major cool factor I almost forgot. You can push the red button on the panel to listen with the unit on or off. A true guy thing indeed. Trust me you will leave it on!

Regards,

Mike

Interesting Mike. Thanks for the information.

[Roc Rinaldi]

If you wanted to measure stuff for yourself, you could put together quite a lot of processing power with $150 and a laptop. Or you could just contact me and I'll rent out my preconfigured measurement rig for $50 + shipping. And then all you have to do is push a button, send me the file, and I can help you interpret the results.

Dr. Who I have a laptop so can I just rent your equipment and use it to do my measurements?

This thread is related to my other thread entitled "Mis-matching subwoofers" http://forums.klipsch.com/forums/thread/916966.aspx

I would love to just push a button, send you the file, and have you interpret the results.

How do we get started?

DrWho, where are you.

How do we get started?