"Official" Audyssey thread (FAQ in post #1) - Page 182

Surrounds are not as critical as your mains, but in theory, you should adjust the mic as you say when testing the surrounds. However, you have to move in and adjust the mic to the new alignment within the gaps between chirps. Audyssey is still recording during this period, and even the sound of you touching the mic might be enough to throw off the readings.

My surrounds are up high like yours. I used to try and re-align the mic between chirps, but now I just set it horizontal (pointing at the ceiling) for all speakers. I haven't really heard any noticeable difference - but then again, I don't have audiophile ears.

Thanks again, Chris. I incorporated this information into the document.

Mark

Edit: 31 July 08: This project is ongoing. To limit confusion, I will posting the most current text on the most currrent page of the thread until we have determined that it is "sufficient" and everyone has had a chance to contribute, if so desired. FYIO: I use the default setting of 30 posts per page.

Mark

I thought it was supposed to be the (exact) center of the listening area?


If possible ensure that each sub is set to the same level (using a sound meter)?

These are the three things I had questions on:

II G. - I saw two recommendations on this, (12" and 24") and the one above was made by Chris, IIRC. Is it OK as written above?

VI B. - Where is the best place to be in the room during the measurements? Does it matter, as long as you are not in between the mic and speaker?

VIII C - Is it OK to modify the L/C/R/Surrounds speaker distance settings? This will not effect anything?

Thanks for any input.

Mark

Seems to me that using multiple subs would be a problem no matter what you do. In setting up wide area paging systems even if all phases and levels were set equally there were still locations that either canceled or added the signal, it was better to run with a frequency offset (not very desirable when listening to audio).

Tilt it so that the beam from the speaker grazes the top surface of the mic. In other words, the vertical axis of the mic is orthogonal to the incident beam.

Hi Kal,

With regard to the sound beam from the speaker, am I correct that you are referring to a sound beam from the speaker's tweeter?

Thanks.

Larry

Yup, the axis of the tweeter.

This is the same as phase, just with only 2 choices: 0 and 180 deg. Just make sure both subs are set the same.

The actual requirement here is that the system doesn't run into its maximum or minimum level when setting the sub levels, which would be inaccurate. Just within +-6 dB will work identically to a 0 dB setting.

Could you point to where this statement was made? Thanks.

It sounds like you are suggesting entering a distance before you run MultEQ. Any distances entered before the measurements are done are ignored. If you are suggesting resetting the distance after the measurements, how do you know what to set it to? You don't want to set it to the average of the physical distances, because that ignores the electrical delay, right? I think the only way to set this distance right, is to run the measurements (perhaps abbreviated, as you suggest earlier for the sub level) with only one sub active, to get an idea of how much electrical delay there is. Then you can run the full speaker setup, and afterwards adjust the distance to the average of the physical distances + electrical distance.

Are there any subs that actually have a delay setting on them, rather than a phase control? If your subs only have phase control, you can't do this.


There is a 2-ft distance between 2-5 and 3-6, not 1-5 and 1-6. It is geometrically impossible to have a 1-ft distance between 1-7 and 5-7 and 2-7 and 4-7 and 2 ft between 1-2 and 1-4. Actually, I think the canonical positions for 7 and 8 are 1-ft to the left (or right) and 1-ft in front of the line between formed by 1, 2, and 3. That gives a distance of 1.4 = sqrt(2) ft between 1 and 7. Of course, the exact positions are not important, but if you're going to put those distances in, you might as well be right.


It might be useful to add here that raising the crossover frequency doesn't affect the channel correction, but lowering the crossover starts to feed uncorrected sound to the satellite. You might also note that the sub filter in MultEQ is much higher resolution than the satellite filters, so it can be beneficial to allow more material to be sent to the sub, i.e. raise the crossover higher than MultEQ's original setting.

The LFE filter is not a crossover, it's a low pass filter.

This is probably a bad idea. Generally, if your distance settings didn't come out right, you have a bad measurement, and should run it over again, making sure that there are no extraneous noises. If you're sure that the measurements are done in silence, and you still get substantial errors in speaker distance, ask a question on the Audyssey thread, so we can all learn what breaks the system!

Where did this come from? Has it been verified?

I've been having a similar problem running MultEQ on my new Denon 1909, except that ALL channels (including the sub) are being set extremely high. I've run it a few different times in a nice quiet room, and each time I've gotten similar results: front speakers +11 or +12 db, center about +10, all three surrounds +12, and sub +10. (The distance measurements have been correct by the way.)

I'm worried that by kicking all the channels up so high, MultEQ had no headroom left to differentiate the channels when necessary. For example, my surround left speaker is a few feet farther away than all the others, so I would have expected the level to be a bit louder. But with most of the speakers already +12, maybe it couldn't go any higher.

I'm sort of new at this -- should I be paranoid that my speaker cables are corroded or something? Does speaker volume decrease when that happens, causing MultEQ to compensate? Last thing in the world I want to do is re-strip 24 wire ends. Thanks!

My fronts have powered subwoofers which I use for LFE (separate input) and I have never had any issues. I just have to make sure they aren't set too loud so they don't interfere with Audyssey's available headroom.

Previously I was using the sub's knob setting (trying to match them) but now I use a sound meter on each one (disconnecting the other) to ensure they are set to the same level before running Audyssey.

It is the center of the listening area being measured. I need to re-write this bullet so it is clearer.

How about this:

F. Place microphone in the primary listening position for the first measurement.
1. Audyssey uses this measurement to set the speaker distances and levels, so the microphone should be placed in the seating position used the most.


I am still not sure exactly how to handle the dual sub setup, as I think we need more input.

Thanks.

Mark

I think seating positions are irrelevant beyond the fact they define the listening area. As such for the first reading the mike should be placed in the exact center of the listening area.

Regarding multiple subs I think it's basically the same as having one outside of placing them in the same position at each side of the room (if possible) and having each of them set to roughly the same level before running Audyssey?

I think Chris and others have stated that the first measurement should be taken from the exact location of where a human sits for the majority of the time, meaning the primary listening _position_.

For example, if you have a three person couch and the "center" would be the middle seat, the primary listening position could also be the left or right seat. In my case, it's the right seat. So putting the mic in the "center" of the listening area would be incorrect as the primary listening position is not the same.

You want the mic were a person would sit most of the time if he or she were alone. The subsequent measurements take into account other positions that people may occupy.

I understand the concept of tuning the sound to the preferred seating position but I'm not sure it's related to sound advice.

My wife uses my dedicated theater perhaps more than myself and almost always sits in the back row far left corner seat. Now if you used that position you might improve her sound more than if you used the center of the listening area. However I tend to think you'd be hurting the other listening positions more than you'd be helping hers.

I will add a note to this effect.



If the system does hit the ceiling or the floor, doesn't Audyssey report a warning? If so, you have to take action before continuing, right?



Right here in this thread, page #1, post #28:

http://www.avsforum.com/avs-vb/showt...40#post9648740



Good point. Yes, Chris said not to reset the distance for the subs. I have to see if I can find where this advice originated from. Perhaps that just should be removed.

Edit: I discovered this recommendation came from the Audioholics review of the stand-alone Audyssey EQ unit. I will post a separate question regarding this.



This was poorly worded, so I will fix it. Adjusting the distance effectively adjusts the time delay.



I will try to fix the drawing. I don't know if I can edit it, since I did not create it.




Thanks. I will add that info.



I will change this. Edit: I was referring to the crossover in the Receiver or Processor, so will clarify the section.



I raised this as a possible issue.



Audioholics Denon AVR-5805 review.

Mark

Here is where Chris covered the topic...

I commented on this board several months ago that I got my most accurate measurements and (subjectively) best results when I wasn't even in the room at all. If you have the ability to sneak quietly into another room as you're pressing "OK" on your remote to start, give it a try and see if it makes any difference to you.

Previously, when I was in the room during the process, I was *behind* the surround speakers in a 5.1 setup, so I was definitely not in the path between speaker and microphone. But it wasn't until I left the room to run Audyssey that my distances were accurate.

I crouch down behind the seats.

I suppose the sight of me bolting out of the room before the chirps begin is probably as silly as you crouching behind your seats!

Oh, the things we do for our hobby/obsession...

I have a Onkyo 885. I have seen reference to chosing the "Audyssey Curve" and the "Flat Curve" when listening to certain inputs. How does one access these "curves"?

Jack

Page 1, post 1, Audyssey 101.

It sounds to me as if the speakers aren't particularly sensitive or there's something very absorptive in the room that's making it require a lot of boost in order to set things to reference level.

What you can do is reduce ALL of the channel levels by the SAME amount, ie by say 11 dB. That will set all of the channels between the -1 and +1 dB range while preserving the current "gaps" between the various speakers. It's the gaps that are important in order to preserve the balance between speakers so you don't want to change them.

If that ends up making the sound levels too low for you when playing a particular source, go to the input settings and add some boost for the input related to the source you're using.

If in fact your speaker wire is corroded under the binding posts you could very well reducing the level plus reflecting a high impedance back to the amplifier. If the wire is that bad and can't be replaced try to clean it (not easy) and tin (solder) a short section (1/2") of the end (in a salt water involvement they use wire/cable with individual strands tined).

Thanks. I will clarify that section.

Mark

The above post from Patrick was the basis for the following section on dual (mono) sub setup in my document:

IV. Dual (mono) Subwoofer Setup
A. Place the subwoofers symmetrically within the room.
B. Place the subwoofers at identical distances from the primary listening position.
1. If this is not possible, enter the average of the two distance measurements.

I re-read the above post, and see that item #1 was based on his use of the stand-alone Audyssey Pro EQ and a Denon 3806 AVR.
However, I think he might also be saying that distance variations between the two (mono) LFE subs might not be detectable.

I am looking for input if I interpreted that correctly and how to better convey the information above.

For example, in my room, the two LFE subs are 4.0 and 4.4 meters from the primary listening position, IIRC. That makes the averaged distance 4.2 meters, which is what I entered manually into the AVP. I have yet to run Audyssey, so am curious as to how it would calculate the distance.

Thanks.

Mark

This is very informative, and a good initiative.

However, I have a specific question for this thread unrelated to the FAQ-process.

I have a new NAD T175. I have run Audyssey successfully, and was please. Everything came out right, distances, trims, and stuff. And it sounded great. But I had to do a few tries before it worked. One time I got Phase warnings on all three front speakers., once my center speaker distance was set to 0.0. Once my left rear gave a 'check type' warning. All of these were subsequent measurements without moving the microphone. Also, the room was very quiet. This was done in an empty house at 5AM, all appliances off, even my PVR and laptop. The levels required for audyssey also varied. Most of the time, all speakers had to be kicked up one 'notch' (the level of the chirp). For one of the measurements all speakers were run at the first chirp level, and for one measurement all were up one level except the left rear, that were up two notches, and it was extremely loud.

I've done many Audyssey setups for clients and friends, and very seldom do Audyssey need to go above the first level, even in a pretty noisy room.

I have quite a bit of acoustical remedies in my room. My reflection points are treated, I have alot of basstraps, and generally give Audyssey good working conditions. Still the results come out very inconsistent.

Any thoughts on why?

Yeah that will make it very hard not to make any noise. I assumed it only recorded during the chirps, i made a bit of noise in between.

Has anyone changed the angle for the surrounds and heard a difference in the final result?

Do you think this is why our wifes frown at our hobby?
However, they don't seem to mind listening or watching.