"Official" Audyssey thread (FAQ in post #51779) - Page 1277 - AVS Forum
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post #38281 of 72099 Old 03-25-2011, 11:57 AM
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Originally Posted by pepar View Post

I don't have it.

But most posts that I read say it is left on for everything.

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Originally Posted by SoundofMind View Post

Speaking for myself, IMO DEQ adds considerable SQ to critical listening of music below reference levels. But most music content is not standardized to film soundtrack level, so a dynamic level offset of 10 to15 is recommended to keep the bass level from being excessively boosted.

Thanks, that's what I'm looking for. I have been struggling with quality of music which seems to vary quite significantly between music content, with boomier bass being one characteristic that seems most rampant. I'm still trying to learn the ropes on the audio reproduction end of things, and haven't really experimented yet with dyneq variations based on content...have just left it on to date.
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post #38282 of 72099 Old 03-25-2011, 11:59 AM
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Originally Posted by tdawson View Post

Hi -

I found that the MultEQ does indeed work without a dedicated center channel in the system (I run a phantom center setup where the front L&R channels handle that information). Thanks for the responses that pointed this out. However, Audyssey DSX will not. Apparently, according to Audyssey, this is because of the particular algorithm used for their DSX program. I wonder if there is a chance that there may be a SW update to change this in the future. After all, Dolby and DTS do not require a center front speaker be present to synthesize surround channel information.

I'd doubt that Audyseey would consider that for DSX. The problem would be that the left and right channel information is used to create the height information (and width information if you ran wides), so without a dedicated centre channel you'd find that voices, or elements of voices, would be put up into the Height speakers, or way out to the sides and in the Width speakers.

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Originally Posted by tdawson View Post

Btw, when I ran the MultEQ setup last night with my current speaker setup which currently includes fronts, front wides and side speakers, I found that it restricted bandwidth for the front wides and sides (to 40 and 50hz) even though I had set them all to full range. Is there any way to force MultEQ to treat all surround speakers as unrestricted full range? If I could get some EQ boost between 20 and 40 hz at the sides as well as the fronts (they are all the same speakers in my setup), that would definitely lend some authority to the low bass and maybe I could dispense with subs while still getting some pretty decent low end SPL. After all, when I get all 8 speakers set up (still finishing the last two), I'll have as much air moving capability altogether as two 15" woofers.

The recommendation from Audyssey is *never* to run the fronts as full range or large. Set the XOs to 80Hz or thereabouts and let the sub(s) take the low end strain, as they are designed to do. It also takes the strain off the AVR by not making it try to force those other speakers to go that low and maybe even has a beneficial effect on the mid-range in those speakers too for similar reasons. I'd say you definitely want a sub or subs regardless of what main speakers you use.

Kind Regards,

Keith
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post #38283 of 72099 Old 03-25-2011, 12:17 PM
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Originally Posted by fotto View Post

Thanks, that's what I'm looking for. I have been struggling with quality of music which seems to vary quite significantly between music content, with boomier bass being one characteristic that seems most rampant...

Of course this all varies per individual preference, equipment, room and specific content. I often listen to CDs at MV -20 to -15. With DEQ engaged, I frequently hear improvements in the imaging and overall clarity, and even width of soundstage. I also find that for 2 ch, lowering the xover for the fronts in Stereo mode from 80 to 60 improves the imaging of the the kickdrum and bass. YMMV. It's fun to tweak!

Yes, I still like playing with Dalis.

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post #38284 of 72099 Old 03-25-2011, 12:33 PM
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Originally Posted by pepar View Post


I don't have it.

But most posts that I read say it is left on for everything.

Off for music for me. I found it distorts classical piano for me.
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post #38285 of 72099 Old 03-25-2011, 12:36 PM
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How does Audessey hande dipole surrounds that are supposed to be out of phase with the fronts for a 5.1 system?
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post #38286 of 72099 Old 03-25-2011, 12:36 PM
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Originally Posted by jmschnur View Post

Off for music for me.

Have you tried different offsets for music?
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post #38287 of 72099 Old 03-25-2011, 12:38 PM
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Originally Posted by SoundofMind View Post

Of course this all varies per individual preference, equipment, room and specific content. I often listen to CDs at MV -20 to -15. With DEQ engaged, I frequently hear improvements in the imaging and overall clarity, and even width of soundstage. I also find that for 2 ch, lowering the xover for the fronts in Stereo mode from 80 to 60 improves the imaging of the the kickdrum and bass. YMMV. It's fun to tweak!

I'm normally in that MV range as well with CD's. Will continue play around with things some more as there's plenty of scenarios to play with.

Not to start another discussion, but after taking REW measurements from 60-120Hz in 10Hz increments, I found that I had the best crossover graphs (for fronts) with the 120Hz setting. 80Hz was second best, but I have left it at 120Hz for now.
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post #38288 of 72099 Old 03-25-2011, 12:41 PM
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Originally Posted by jmschnur View Post

How does Audessey hande dipole surrounds that are supposed to be out of phase with the fronts for a 5.1 system?

Supposed to be out of phase with the fronts, i.e. the LCR speakers? The front- and rear-facing drivers of dipole speakers are wired out of phase ... is that what you are thinking of?
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post #38289 of 72099 Old 03-25-2011, 12:43 PM
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Originally Posted by pepar View Post

Have you tried different offsets for music?

Yes. For old blues an offset of 5 is nice. But for SACDs it is better off for me.
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post #38290 of 72099 Old 03-25-2011, 12:44 PM
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Originally Posted by pepar View Post

Supposed to be out of phase with the fronts, i.e. the LCR speakers? The front- and rear-facing drivers of dipole speakers are wired out of phase ... is that what you are thinking of?

Yes Does Audyssey leave the phase alone for this case.
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post #38291 of 72099 Old 03-25-2011, 12:56 PM
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Originally Posted by jmschnur View Post

Yes Does Audyssey leave the phase alone for this case.

AS far as I know, it does. I don't recall reading anything about Audyssey ever changing the phase .. just frequency response.

Anyone?
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post #38292 of 72099 Old 03-25-2011, 12:56 PM
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Originally Posted by kbarnes701 View Post

The recommendation from Audyssey is *never* to run the fronts as full range or large.

Except when Chris says otherwise?
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post #38293 of 72099 Old 03-25-2011, 12:57 PM
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Originally Posted by jmschnur View Post

Yes. For old blues an offset of 5 is nice. But for SACDs it is better off for me.

I don't have it, but then I listen to everything loud so I'm not sure how much it would be doing anyway. It'll be in my next pre/pro and I'll get to try it.
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post #38294 of 72099 Old 03-25-2011, 01:00 PM
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Originally Posted by bodosom View Post

Except when Chris says otherwise?

I don't read that as "otherwise." "No Audyssey benefit in forcing speakers to Small" is not the same as setting a crossover in a bass-managed system because the sub is likely to do the best job reproducing the lower octaves, main amp headroom can be gained and subs are more likely to be located to produce lessened room modes.

Jeff
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post #38295 of 72099 Old 03-25-2011, 01:03 PM
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I'd doubt that Audyseey would consider that for DSX. The problem would be that the left and right channel information is used to create the height information (and width information if you ran wides), so without a dedicated centre channel you'd find that voices, or elements of voices, would be put up into the Height speakers, or way out to the sides and in the Width speakers.

I would hope something like this shouldn't confuse Audyssey since it should still have the center channel information to process, regardless of whether the receiver amplifiers are configured to implement the center front as a discrete channel or not.
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post #38296 of 72099 Old 03-25-2011, 01:07 PM
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Quote:
Originally Posted by jmschnur View Post

Yes Does Audyssey leave the phase alone for this case.

Quote:
Originally Posted by pepar View Post

AS far as I know, it does. I don't recall reading anything about Audyssey ever changing the phase .. just frequency response.

Anyone?

Well, it's entirely correct to call time alignment phase adjustment but in the case of dipoles (or any other single cabinet arrangement of speakers) if the input is a single pair of connectors how can a generic AVR do anything about the phase relationship of the entire box? I'm sure someone built a specialized controller mated to a dipole that would do all sorts of magic but as a practical matter the best you can hope for is a dipole/bipole/monopole switch.
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post #38297 of 72099 Old 03-25-2011, 01:09 PM
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Originally Posted by tdawson View Post

I would hope something like this shouldn't confuse Audyssey since it should still have the center channel information to process, regardless of whether the receiver amplifiers are configured to implement the center front as a discrete channel or not.

Maybe it needs to "see" the center channel content to subtract that from the L&R Wides because of CC content that is shouldered in the L&R?
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post #38298 of 72099 Old 03-25-2011, 01:16 PM
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Audyssey does not set crossovers. Your receiver does. Audyssey measures the speakers' in room response. It ignores all settings in doing so. Then it reports the measured -3dB frequency extension of your speakers to the receiver, which uses its own logic to set large/small/crossover. Nothing stops you from going back and changing things. But you should be aware that Audyssey will not correct FR anomalies below the measured -3 dB point. Up to you . . . but how your speakers measure in your room is really how they measure, and IMO specs to the contrary cease to be of great importance if the actual in room FR differs for whatever reason.

Ok. But what if, not all that hypothetically, somebody uses a speaker that is very capable down to 30 hz, but due to room resonant modes, the response is down several db between 30 and 60hz at the measurement point? Wouldn't it be much more satisfactory to equalize the bottom octave flat than to further attenuate it? Sort of a 'Where's my bass, dude?' scenario.

Btw, your explanation appears to leave open the possibility that Audyssey would eq flat the surround channels down to the bottom octave just as it would the front channels, but it would be left to the receiver HP filters to afterward provide all the effective attenuation. If this is the case and given that I can defeat the receiver's filters, that might be satisfactory as long as I run w/o subs.

I should mention that all my home brew HT speakers are specifically designed not to sustain any damage within my receiver's power envelope at any frequency - only some speaker distortion may occur at the highest power my receiver is capable of since Xmax may be exceeded but Xmech won't be reached.
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post #38299 of 72099 Old 03-25-2011, 01:17 PM
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Originally Posted by pepar View Post

I don't read that as "otherwise."

I've somewhat abstracted the question and answer because the main point remains that the proper decision involves a plethora of factors and absolutes (e.g. *never*) don't always apply.

I suspect I will continue to listen to stereo music sources with my fronts set to full.
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post #38300 of 72099 Old 03-25-2011, 01:24 PM
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Originally Posted by tdawson View Post

Ok. But what if, not all that hypothetically, somebody uses a speaker that is very capable down to 30 hz, but due to room resonant modes, the response is down several db between 30 and 60hz at the measurement point? Wouldn't it be much more satisfactory to equalize the bottom octave flat than to further attenuate it? Sort of a 'Where's my bass, dude?' scenario.

Btw, wouldn't your explanation leave open the possibility that Audyssey would eq flat the surround channels down to the bottom octave just as it would the front channels, but the receiver HP filters would afterward provide all the effective attenuation? If this is the case and given that I can defeat the receiver's filters, that might be satisfactory as long as I run w/o subs.


Read more carefully. Audyssey does not attenuate, it stops making corrections. If Audyssey sees the -3dB point as 30 Hz, it'll correct down to 30 Hz, and presumably the receiver will leave them large as most have 40 Hz as the low point for a large setting.

Crossovers are a different matter. If you are using bass management- - using your sub, which can theoretically be placed for best bass performance - - to handle all the low frequencies, you WANT to roll off the non-subs so you don't have overlap and a FR bulge.

And if you, as many folks here do, set your crossover higher than the -3dB point identified by Audysey, you are, by definition, "throwing away" some Audyssey-corrected frequency response in the bass frequencies of the non-subs. Nobody's been struck by lightning for doing it yet. Until the advent of MultEQ32, because the sub filter has more filter points available, the usual thought has been that the bass will be better served by going through the better-corrected sub channel. That particular issue vanishes with MultEQ32, however.
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post #38301 of 72099 Old 03-25-2011, 01:33 PM
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Quote:
Originally Posted by tdawson View Post

Ok. But what if, not all that hypothetically, somebody uses a speaker that is very capable down to 30 hz, but due to room resonant modes, the response is down several db between 30 and 60hz at the measurement point? Wouldn't it be much more satisfactory to equalize the bottom octave flat than to further attenuate it? Sort of a 'Where's my bass, dude?' scenario.

Btw, your explanation appears to leave open the possibility that Audyssey would eq flat the surround channels down to the bottom octave just as it would the front channels, but it would be left to the receiver HP filters to afterward provide all the effective attenuation. If this is the case and given that I can defeat the receiver's filters, that might be satisfactory as long as I run w/o subs. I should mention that all my home brew HT speakers are specifically designed not to sustain any damage within my receiver's power envelope at any frequency - only some momentary distortion may occur at the highest power my receiver is capable since Xmax may be exceeded but Xmech won't be reached.

Audyssey runs the sweep from low frequency to high frequency and if the FR bounces back after a dip, Audyssey sees it. AFAIK, nobody's run into a problem where Audyssey failed to distinguish between a FR dip and the beginning of speaker rolloff.

If your speakers can reach 20 or 30 Hz before their measured -3dB Point, Audyssey will correct to those levels. It does not attenuate anything. It just stops correcting, so it doesn't boost a speaker's response by 9 dB in a frequency region where the speaker is not capable and blow that speaker up. If Audyssey reports a 20 or 30 Hz -3 dB point for a speaker, the receiver will set that speaker as large (AFAIK, recently they pretty much all use 40 Hz as the "Large" cutoff, however they describe it).

If you set a crossover above your speaker's -3dB point (and MANY here say they do) then, yes, there is some Audyssey-corrected FR in the non-subs that gets thrown away. Nobody's been struck by lightning for doing so AFAIK. It allows you to get the bass from a speaker that can be placed at an optimal location in the room for bass reproduction. With systems below MultEQ32, it gives you much more precise filtering (the sub channel has more filter points) for the bass, which tends to really need it. This goes away with MultEQ32, which has the higher resolution in all channels.
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post #38302 of 72099 Old 03-25-2011, 01:35 PM
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Quote:
Originally Posted by pepar View Post

I don't read that as "otherwise." "No Audyssey benefit in forcing speakers to Small" is not the same as setting a crossover in a bass-managed system because the sub is likely to do the best job reproducing the lower octaves, main amp headroom can be gained and subs are more likely to be located to produce lessened room modes.

Jeff

So in this case we are talking about setting the bass management ahead of running the Audyssey calibration right?

I am not exactly sure how I could do this... line level crossovers?

The configuration that I am thinking is a AVR (Onkyo NR3007) and external amplifiers to run a pair of subs...

Al
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post #38303 of 72099 Old 03-25-2011, 01:47 PM
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Audyssey runs the sweep from low frequency to high frequency and if the FR bounces back after a dip, Audyssey sees it. AFAIK, nobody's run into a problem where Audyssey failed to distinguish between a FR dip and the beginning of speaker rolloff.

Thanks for the additional information. This gives me food for thought - how I can fake out the Audyssey algorithm and 'make' it provide correction down to the frequency I want. What occurs to me is to fabricate some small 'bandpass' tuned speakers at about 20 hz that will be driven in parallel with the co-located surround channels. Audyssey might then detect what it interprets as a 'FR bounce back' and eq down to 25 hz or so, which is what I want for now. Then remove the little bandpass guys.

It's a bit of trouble but should be worth it to augment the system LF response. Frankly, I really don't need or want the purported 'protection' that these filtering or 'non eq-ing' schemes are intended to offer and want to fully evaluate my speakers sans subs before deciding whether I need to introduce more monkey coffins into my HT area.

Another reason is that I suspect that it might be quite a bit more realistic sounding to have the full frequency response originate from each speaker rather than have all the LF coming from a single location in the HT. Taking full advantage of the Audyssey frequency AND time domain correction across the entire frequency range for each channel, IOW. I doubt that Audyssey does this with a single sub in a system.
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post #38304 of 72099 Old 03-25-2011, 02:01 PM
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Originally Posted by pepar View Post

AS far as I know, it does. I don't recall reading anything about Audyssey ever changing the phase .. just frequency response.

Anyone?

Audyssey doesn't do anything weird with my dipoles. Just takes them in its stride.

Kind Regards,

Keith
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post #38305 of 72099 Old 03-25-2011, 02:05 PM
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Originally Posted by bodosom View Post

Except when Chris says otherwise?

That's not a recommendation to run the speakers as full range. What he is commenting on is the filter resolution which, with XT32, is the same right through the frequency spectrum, so, as he says there, there is no benefit to EQ by setting the speakers to full range, unlike the benefit gained with XT.

If you take the concensus of Chris's comments on setting speakers to full range, you'll see he doesn't recommend it. I can't be bothered to find a dozen quotes to support that, but if you schlep along to the Audyssey site, they're there.

EDIT: Just for you:

This is what Chris has to say:

"If you have a subwoofer in your system, you should always use bass management in the AVR. Unfortunately this is not always the default setting and several manufacturers still insist on setting speakers to “Large” or “Full Range”. Doing so will prevent bass from being redirected to your subwoofer from the satellite channels. Audyssey recommends to manually change all speakers to “Small” (i.e. set a crossover frequency for each speaker in the manual settings menu) thus enabling proper bass management."


"Always" use bass management is the same as saying "never" set the speakers to Large.

And this is just one of the many places he's said it:

http://ask.audyssey.com/entries/74454-bass-management



Kind Regards,

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post #38306 of 72099 Old 03-25-2011, 02:06 PM
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Quote:
Originally Posted by pepar View Post

I don't read that as "otherwise." "No Audyssey benefit in forcing speakers to Small" is not the same as setting a crossover in a bass-managed system because the sub is likely to do the best job reproducing the lower octaves, main amp headroom can be gained and subs are more likely to be located to produce lessened room modes.

Jeff

Yeah - Chris has only said that about a thousand times

Kind Regards,

Keith
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post #38307 of 72099 Old 03-25-2011, 02:09 PM
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Originally Posted by mastermaybe View Post

I'd be interested to hear the drawbacks of such a feature

Some I mentioned previously, some I haven't:
You would lose your HPF protection on the analog multi-channel inputs (on the vast majority of AVRs, maybe all but one?);
You would lose the ability to use infrasonic devices (buttkickers, etc.);
The vast majority of subs typically used already have a HPF (if they need one). So in most cases, you'd be double-filtering (which is considered bad practice) and you could end up losing extension unnecessarily;
It would be an imprecise method, because Audyssey wouldn't know whether or not the sub NEEDED a HPF. Does the sub have one (or doesn't need one), and the -3db point is the natural intended rolloff, or is it an unprotected ported sub that should be rolled off aggressively from that point? Sealed subs typically roll off at 12db/octave, while ported subs should typically be rolled off around 24db/octave (or other values for other alignments). How much of the rolloff curve is due to the sub, and how much is offset by room gain? How would Audyssey know what rolloff curve (if any) is appropriate?
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... especially considering that a decent sum looking into high end apps of Audyssey XT 32 may very well have passive subs and amps that are not so easily configured to accomplish the goal.

Me being the type that "enjoys textual combat", I'd argue that point. If you look through the "Subwoofers, Bass, and Transducers" forum, I think you would find that very few have subs that need a HPF, but don't have one. Earlier you indicated that a DSP with the appropriate filters can be had for $50 (I don't know, I've not searched for them). If so, I would suggest that anyone looking in to a high end passive sub that needs a HPF would much prefer one that could be tuned to the specific needs of that sub, rather than letting Audyssey guess at what it should be. Is it really worth all the potential negatives to save $50 on (what I perceive to be) a very small percentage of applications?

It it were done as a feature that could be turned on of off, then many of those negatives would go away. But my opinion is, that function is best served by the subwoofer circuit, and therefore there would be little value in "marketability" of that feature from Audyssey's perspective, especially considering the additional liability they'd be taking on.

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post #38308 of 72099 Old 03-25-2011, 02:16 PM
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Originally Posted by tdawson View Post

I would hope something like this shouldn't confuse Audyssey since it should still have the center channel information to process, regardless of whether the receiver amplifiers are configured to implement the center front as a discrete channel or not.

The problem is that when you have a centre channel, dialogue is mainly confined to that channel. There isn’t much dialogue in the L&R channels, other than for special, off-stage, effects etc. So when DSX processes the L&R channels, it doesn't start to get dialogue up in the Height speakers or out in the wide speakers. If you run a phantom centre, dialogue is generated in the L&R speakers to create a phantom centre image. So when DSX looks at the L&R channels, there's dialogue there. You really don't want any dialogue in the Height or Wides.

Chris Kyriakakis is also resolutely opposed to running a system without a centre channel for other good reasons too:

"I don't consider the center speaker as an optional improvement. If your goal is to listen to the content the way it was created then it is an absolute necessity. Stereo was invented at Bell Labs in the 1930s with three channels! Left, Center, Right. It was because there was no medium to deliver proper stereo to consumers that it was limited to two channels on LPs. There is nothing perceptually correct about two-channel stereo because there is really no correspondence between the two speakers and our two ears. In fact, there are frequency response problems that are caused by phantom images. Sound from the left speaker reaching the right ear interferes with sound from the right speaker reaching the right ear because they arrive at different times. The same happens on the other side. This interference causes response problems in the midrange that are solved by a real center speaker. For movies, the majority of the content is in the center channel. It requires the most dynamic range and proper directivity. It is unfortunate that the industry in the early days tried to diminish the importance of the center speaker. "

Kind Regards,

Keith
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post #38309 of 72099 Old 03-25-2011, 02:35 PM
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Hi, Keith -

Thanks for the response. I understand the advantages of having a center channel, and if you can park the center channel speaker directly behind a projection screen and use Audyssey to correct its response, it's a no-brainer.

But what if, like myself, you have a very large DLP display and the L & R front speakers are vertically centered with the screen? If the center channel is put below the screen at the center, that's over a 2 foot average vertical offset and sure to be quite noticeable, if not distracting with material having dialogue where the acoustical height can be nearly 4 feet below the visual height for the center channel. And how about pans from either Left and Right to and from center? True, a phantom center is prone to off angle comb filtering and some cross feed problems, but the other issues I mentioned would seem to be much less significant using that approach.

This is not to say that I won't eventually construct a dedicated center channel for my HT setup. I most likely will. But, it's not something that I expect will be an unmitigated improvement for my setup.
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post #38310 of 72099 Old 03-25-2011, 02:43 PM
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Originally Posted by tdawson View Post

Hi, Keith -

Thanks for the response. I understand the advantages of having a center channel, and if you can park the center channel speaker directly behind a projection screen and use Audyssey to correct its response, it's a no-brainer.

But what if, like myself, you have a very large DLP display and the L & R front speakers are vertically centered with the screen? If the center channel is put below the screen at the center, that's over a 2 foot average vertical offset and sure to be quite noticeable, if not distracting with material with dialogue where the acoustical center can be nearly 4 feet below the visual center. And how about pans from either Left and Right to and from center? True, a phantom center is prone to comb filtering problems, but the above would seem to be relative non issues with that approach.

Can you lower the L&R speakers somewhat? The usual recommendation I think is that the tweeters should be at ear height when you are seated normally. If you speakers have good off-axis response, lowering the L&R could perhaps make it easier to get a centre channel more 'in line' with them. I certainly appreciate the need to do that as far as it's practical.


Quote:
Originally Posted by tdawson View Post

This is not to say that I won't eventually construct a dedicated center channel for my HT setup. I most likely will. But, it's not something that I expect will be an unmitigated improvement for my setup.

Sure - there are practical difficulties sometimes in placing a centre speaker, but those difficulties don't change the nature of the problems caused by not having a centre speaker. I think that with careful placement and with angling the centre speaker up towards the MLP, not to mention the pyscho-acoustic effect of our brain locating sounds where the visual stimuli say they 'should' be coming from, it's generally possible, for most people, to integrate a centre speaker into their system. But then my centre channel is immediately below the screen and there certainly isn’t a 4 foot gap between it and the 'talking heads' on screen.

My ideal would be an AT projection screen with a really good centre speaker located in the middle, behind it. But sadly I have nowhere near enough space for that at this time. For most of us, HT is all about compromises and making the best of what we have I guess.

Kind Regards,

Keith
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