"Official" Audyssey thread (FAQ in post #1) - Page 1802

I might try to dig this up later, but Markus posted some very compelling evidence (both rhetorical and with measurements) that the separate "time alignment" of dual/multiple subs isn't necessary. Furthermore, I believe he argued that it was even somewhat nonsensical to think about "time alignment" with subwoofers in the same way that we think about satellite speakers, given the size of the wavelengths involved.

I think the key (as you two note above, and which Markus constantly stressed) is to FIRST place the two subs in such a way that seat-to-seat variance is minimized. Then you can run EQ on top and should get the best results.

"I believe he argued that it was even somewhat nonsensical to think about "time alignment" with subwoofers in the same way that we think about satellite speakers, given the size of the wavelengths involved"

+1!

Sooo..its not that important to set separate distances for 2 subs?

But the wavelengths for the upper end of a typical subwoofer's range aren't that massive, as described here. Those would be the frequencies I'd worry about, especially if my subs had a 7+ foot difference from MLP that I could not correct for within the AVR.

Agree that for 20 Hz, it's completely irrelevant!

I think there's some "tolerance" though I couldn't say what the max temporal delta would be. As you allude, it is likely frequency-dependent. I know Craig's system is ... off the chain.

When setting up Audyssey I notice it does not set the sub crossover automatically. In other words if it is already set to 120 or 80 before running Audyssey it leaves it at whatever setting it was on last. Isn't Audyssey supposed to set it automatically?

Sub "crossover" ... ? Do you mean the LPF on the LFE? If so, that should be at 120Hz. There's some disagreement on that setting, but that's my recommendation.

Jeff

it's not a crossover. Read this: http://www.avsforum.com/avs-vb/showp...count=51803#c5

Yes I meant the lpf on the lfe but speaking of crossover on my mains is always higher than 80 after Audyssey is done. I was told I cannot lower only raise crossover.

well, just read the rest of the link I gave you and you will know what to do

Somehow Audysey sets the speaker crossovers to anything but 80hz.

I've become very interested in the new 818 and have searched it out at all the usual reputable on-line sources and have yet to see it at "under a $1000/grand" that you repeatedly mention. Matter of fact it comes in one buck shy of $1100 at the big 'A'. It's likely it will be discounted further as it becomes widely available but it seems that is not the case as of now. Or, it could also become so popular that if retailers can't keep it in stock it won't be discounted at all.

First, Audyssey is measuring and passing that information along to the processor which sets the crossovers based on the measurements and the manufacturer's criteria. Audyssey isn't doin' the settin'.

Second, the resulting crossovers are based on the measurements of how your speakers perform in your room based on their interactions with the room ... the walls, ceiling and floor mainly. If you move speakers, Audyssey should be re-run.

HOW DOES IT SOUND?

Jeff

It sounds nice. I just hear alot about changing crossover to 80hz and in my case I guess I can't because Audyssey sets the mains above 80. (Most likely because my speakers can't do 80) One thing I don't buy is dynamic volume. I think it does NOT eliminate volume spikes like adversized.

Read this entire section of the FAQ and it should make it more clear:


C. Crossover Settings (click here)

But that's just it...you can change them down to 80...no one is holding a gun to your head. As long as you fully understand the implications of the change, and can accept them, you're free to throw the guidelines to the wind and try it out for yourself to see how much better/worse it sounds. You can always set it back to how it was...nothing will "break" through this kind of experimentation.

The implications in this case are that Audyssey does not create EQ filters below where the AVR sets the crossover. So you will have a small but important band of uncorrected frequencies. However, that may be less objectionable to you than being able to easily localize a subwoofer because the crossovers is set to 100 Hz for instance.

Another implication is that your speakers can't reproduce sound at 80 Hz at an adequate level, else the crossover would have been set lower through the calibration routine. By lowering it, you're asking the speakers to perform better than they can in the bass region with respect to where they are in the room. Again, that may be less objectionable than being able to localize the subwoofer, though.

Most folks here will tell you to not lower the crossover due to those reasons. I agree but caveat it with an earnest encouragement to try it out for yourself, and see if it sounds better or worse to you. It may be that entirely through coincidence, that band of uncorrected frequencies needs very little or no correction anyway, and that a dip in the bass sounds more to your preference, in which case you're not losing anything by doing it.

I actually lowered my center channel crossover from 90 Hz to 80 Hz for no other reason than to match all the other speakers. Guess what...I could not hear a difference! ;-)

Did you expect to hear a difference?

I wasn't sure if I would or not, but it still sounds fabulous to me after the change though I haven't spent a lot of dissecting it; regardless, my experience wasn't utterly ruined by bucking the consensus on that topic.

My point is that sometimes the accumulated wisdom here can come across as "Audyssey law" rather than guidelines which then scares folks away from natural experimentation which is essential to the learning process. The guidelines are sound, but when posters say, "I was told I cannot lower only raise crossover", that just feels a bit more totalitarian than helpful I think.

Try watching the start of something like Transformers, where Optimus Prime's voice is heavy in the center and see if you can tell a difference.

Bill

On second thought, since I use Pro for calibrations, I probably am getting correction in the 80-90 Hz band (though it still begs the question if my CC can reproduce that range with any sort of authority).

Regardless, I have not noticed any "lack" in the CC whatsoever.

Until there is more than a basic understanding, that is a safe guideline to operate under.

Jeff

I have a seemingly silly question, but I'm starting to thing the answer may help me clear up a mystery. I have a set of old Boston Acoustic floorstanders (A-150) that have a 10 inch woofer that I'm using as my front mains. These speakers do a great job on the low end (in direct mode, for example). However, when I run Audyssey on my Denon 1910, I've found that it sets the crossover for my BAs at 110, the same as my much smaller (3.5 inch "woofer") cheapo surrounds. I know the BAs can produce great low end at good volumes, so I'm confused by this finding. I'm starting to wonder if Audyssey (or possibly the Audyssey mic) in my Denon isn't functioning correctly. This brought me to the Audyssey "chirp" sound. My understanding is that the chirp is a very fast full sweep. But what I hear doesn't sound like a full sweep; I only hear the higher frequencies. This may just be my perception. Do other listeners hear a full sweep? I'm feeling this may be the problem, but since I've only run Audyssey on my system, I'm not sure if what I'm hearing is normal. Thanks.

LOL, that is PRECISELY what I used as one of my tests for the center channel (amongst other material) that made me decide to get a better (matching) center that could dig deeper.


Max

That's a good point. The FAQ is very adamant about *never* lowering the XOs. When I get a round tuit I will change the FAQ section to reflect the points you made in your earlier post (localising bass being the worse of two evils etc).

Yep, I hear a full sweep. It IS fast though. If you hear the subwoofer chirps they sound perceptually softer than the satellite chirps due to our hearing sensitivity at different frequencies, but with my setup, all my speakers play down to 20-30's Hz and I hear the low end of the chirps at the beginning of each chirp.


Max

This is what I was thinking. I'm going to run it when I get home and see if a closer listen reveals the low end part of the sweep. I didn't expect it for my surrounds (or my center, although that also came in at a lower crossover freq than my BAs), but I was expecting to hear it from the BAs and didn't.

Hi tandy and all, please allow me to comment a bit on the above highlighted and underlined part. Well, actually after Audyssey reports the -3 dB (F3) point to the AVR (which value we don't know) the AVR chooses a closest upper preset crossover frequency. For example if the AVR like my Denon has presets of 40/60/80/100/120, etc., the C/O will be set to say 100 Hz in any case the F3 point measured by Audyssey falls between 81 and 100 Hz. In other words the C/O set by the AVR is not equal to the F3 point measured by Audyssey but can vary quite a bit (it is always above the F3 but we don't know how much above it is!), while Audyssey does create filters down to the F3 point regardless of the upper closest C/O set by the AVR. In the above example 81 Hz or 100 Hz is quite a difference I may say. Most of male voice fundamental frequencies fall into that region and if left unEQ'd may result is colorization or masking, etc. (too complex an issue IMHO). Remember, we are in the Audyssey thread and not in the HTIB thread, no pun intended to guys over there, so here we need to look very closely into every detail!


Whaddaya and others think of the above reason? Let's talk!

That is a good point, that Audyssey actually corrects down to the -3db point it measures--not the crossover automatically selected by the AVR--so I mis-stated that in my posts above.

Just saying that before Audyssey existed, folks were free to select whatever crossover they wished. Most selected 80. Now that Audyssey provides us with a much more scientific way to select a crossover, it doesn't necessarily mean that our right to choose is henceforth forever lost. I own and command the gear...it doesn't own and command me (I think? ;-)) Anyway, just like I can choose to put my surround speakers on the floor, or put my main speakers at 45 degrees instead of 60 degrees, I ultimately have final say in how my theater is to sound. As long as I know what I'm compromising by taking an action the runs counter to the wisdom of the day, where is the harm, especially if that action provides benefits in other areas that are more important to me.

Me personally, I would never run a crossover above 80 for various reasons. Obviously I would try to figure out why the crossover was being set so high, especially if I had decent loudspeakers that should play into that range, but if no good answers became apparent, I would rather have a "hole" in my EQ than 120 Hz crossovers. 95% correction is still way better than none.

What are your further thoughts about this?


Just so long as folks don't feel like they are going to actually "break" something by lowering the XO, I think it's fine as written--you already do a wonderful job in the FAQ explaining the whys of the recommendations which is really all I'm after. If folks read one sentence then stop before they get the complete picture, that's on them not the expert. Heck, you recently broke an Audyssey "law" by dialing in 180 degree phase on your subwoofer and it never sounded so good! I'm glad you did, too! ;-)

Safety schmafety... ;-)

I think the basic premise should be, "Here is the current recommendation based on everything collectively known about a topic. Employ it or not, makes no difference to me, but if you find a better way, please share it to advance our knowledge."

Therein lies the true value of these forums beyond a simple help desk. ;-)

People don't read if there are too many words. So we K.I.S.S.