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Hi,

With Audyssey MultiEQ XT32 it's possible to use several measurement points, up to 9 I believe. But what if you have a quite narrow sweet spot where people in reality actually will be seated when listening. Is it still a good idea to use all those measurement points during Audyssey calibration?

And in the extreme case, where the Main Listening Position (MLP) is the only place where someone ever will be seated, should that in fact be the only measurement point?

I'm thinking that additional measurement points may in fact result in a worse result, since Audssey then will have to do some compromise trying to make it sound good or at least "ok" at all measurement points. And when trying to achieve that it'll have to make the sound at the MLP not ideal. Is that correct?
 

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In the extreme case, then absolutely yes I would think that you should only measure that spot. I would even probably do two or three measurements in that same spot--more measurements + averaging will always be more accurate. Of course it already runs the same pink noise sweep 6 times for each channel.

Keep in mind that it does some form of averaging at the end to actually generate the real-time processing coefficients. So if you will be sitting in one spot 2/3 of the time, and a second spot 1/3 of the time, then you might consider doing 2 runs in your sweet spot, and 1 run in the secondary spot.

Just play with it and see what sounds good.
 

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I've gotten good results taking four Audyssey measurements. I put the mic on a tripod in the MLP for the first & last measurements. For the middle two I place the mic 1.5' either side of the MLP. My thoughts behind doing this are that I only really care about the response at the MLP, but I don't want Audyssey over-correcting the high end response. For example, if there's a peak near 12 KHz at the MLP but it doesn't exist at one or both sides, then I'd rather not have Audyssey correct that issue.

Taking FR measurements with & without Audyssey correction is the best way to tell if you've accomplished your goals. Here are mine (Audyssey Blue, No EQ Orange):
 

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I've had the best results by using only 3 mic positions - MLP, 6" right of MLP, 6" left of MLP.

And, since we're showing off graphs. :)


 

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Hi,

With Audyssey MultiEQ XT32 it's possible to use several measurement points, up to 9 I believe. But what if you have a quite narrow sweet spot where people in reality actually will be seated when listening. Is it still a good idea to use all those measurement points during Audyssey calibration?

And in the extreme case, where the Main Listening Position (MLP) is the only place where someone ever will be seated, should that in fact be the only measurement point?

I'm thinking that additional measurement points may in fact result in a worse result, since Audssey then will have to do some compromise trying to make it sound good or at least "ok" at all measurement points. And when trying to achieve that it'll have to make the sound at the MLP not ideal. Is that correct?
Audyssey doesn't try "...to make it sound good or at least "ok" at all measurement points." It analyzes all the measurements and looks for problems that are common to groups of measurements. It only tries to fix issues that show up in multiple measurements. If you place the mic in one position for all the measurements, it will find identical problems in all the measurements and correct them. You'll get very flat response in that one location. However, it's not likely that you'll "like" that result.

It doesn't hurt anything, or cost anything except your time to try, so feel free to give it a shot and see if you like it. If not, you can always go back and redo the measurements the *right* way.

Craig
 

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Audyssey doesn't try "...to make it sound good or at least "ok" at all measurement points." It analyzes all the measurements and looks for problems that are common to groups of measurements. It only tries to fix issues that show up in multiple measurements. If you place the mic in one position for all the measurements, it will find identical problems in all the measurements and correct them. You'll get very flat response in that one location. However, it's not likely that you'll "like" that result.

It doesn't hurt anything, or cost anything except your time to try, so feel free to give it a shot and see if you like it. If not, you can always go back and redo the measurements the *right* way.

Craig
The old question related to what Craig is saying is, even if you want to EQ for only one position: Do you keep your head in a vice while listening? And even if you could somehow, your ears are about 6" apart. So, if you measure only one point dead center between your eyes, there may be problems 3" to the left or to the right. Among other things, it is almost (make that entirely) certain that the reflections coming from one side are not identical to the reflections coming from the other side. Of course, not all reflections are bad. But Audyssey may be EQing the two sides of your head slightly differently.

The conventional wisdom is to give Audyssey at least a bubble of space, how big is up to you, around your head to sample before correcting. Of course, when Alan, and some others say that they have gotten great results with as few as three mic. positions, I believe them. I seem to recall one respected Audyssey poster who said that he got extremely consistent, and good, results with only one mic. position. But I also believe that he had a heavily treated room, and I know that he and some of the others who get good results with limited mic. positions are also measuring their results with REW or the like.

I wouldn't hesitate to experiment just for fun, but odds are you will do much better by following normal protocols.
 

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Since Audyssey's measurement resolution increases with each measurement point, you'd want to use as many as possible. However, where you take them is up to you. It makes little sense to do multiple measurement positions without moving the mic, so move it, at least a little. I often will "weight" a certain seat with more measurements around it, with only single measurements at other listening positions. The results will tend to favor that LP. But I always use pretty much all available measurements.

How dramatic Audyssey's results are is definitely a function of the quality of the speakers and room. I spent several hours in a really good room with really good speakers once, wondering why switching Audyssey on and off made little if any difference...before I realized, the system and space was pretty darn good already. In that kind of room, a single measurement point will result in more audible change switching Audyssey in and out because it is responding to single point issues that can be fairly radical. That kind of EQ is technically wrong, but clearly audible, and probably why people (with good speakers and rooms) seem to prefer fewer measurement positions.

I budget positions based on the most likely seating and usage. So if there's a favorite three or four seats, they'll get more measurements around them than the others. But again, I'll always use all available measurements one way or other.

BTW, the multiple chirps you hear at each measurement position for each speaker are not multiple measurements, they are integrated into a single measurement, with all chirps from a given speaker being combined. Multiple chirps improves the signal to noise ratio of the measurement, hence the 4 or 6 chirps per speaker per position. Fuzzy Clustering is then applied when all measurement positions (per speaker) are combined.
 
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Since Audyssey's measurement resolution increases with each measurement point, you'd want to use as many as possible. However, where you take them is up to you. It makes little sense to do multiple measurement positions without moving the mic, so move it, at least a little. I often will "weight" a certain seat with more measurements around it, with only single measurements at other listening positions. The results will tend to favor that LP. But I always use pretty much all available measurements.

How dramatic Audyssey's results are is definitely a function of the quality of the speakers and room. I spent several hours in a really good room with really good speakers once, wondering why switching Audyssey on and off made little if any difference...before I realized, the system and space was pretty darn good already. In that kind of room, a single measurement point will result in more audible change switching Audyssey in and out because it is responding to single point issues that can be fairly radical. That kind of EQ is technically wrong, but clearly audible, and probably why people (with good speakers and rooms) seem to prefer fewer measurement positions.

I budget positions based on the most likely seating and usage. So if there's a favorite three or four seats, they'll get more measurements around them than the others. But again, I'll always use all available measurements one way or other.

BTW, the multiple chirps you hear at each measurement position for each speaker are not multiple measurements, they are integrated into a single measurement, with all chirps from a given speaker being combined. Multiple chirps improves the signal to noise ratio of the measurement, hence the 4 or 6 chirps per speaker per position. Fuzzy Clustering is then applied when all measurement positions (per speaker) are combined.
This is what I was thinking. On my 3 seats,

Option 1 : 2 measurements at each (altering position between each measurement) position
Option 2 : 1 measurements at each, then 1 each to left and right of MLP (between MLP and side position) and remaining measurements at MLP again.
 

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This is what I was thinking. On my 3 seats,

Option 1 : 2 measurements at each (altering position between each measurement) position
Option 2 : 1 measurements at each, then 1 each to left and right of MLP (between MLP and side position) and remaining measurements at MLP again.
You want to give Audyssey as much information as possible about the acoustics of your room. Therefore, do all available measurements. If you want to weight the MPL somewhat, you can group some measurement positions close to the MLP. However, there is NO benefit to duplicating measurement positions, and in fact, it is detrimental. Here is the mic pattern I use:



Here is the spatial average of measurement positions 1, 2 and 3 post Audyssey:



Craig
 
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This is what I was thinking. On my 3 seats,

Option 1 : 2 measurements at each (altering position between each measurement) position
Option 2 : 1 measurements at each, then 1 each to left and right of MLP (between MLP and side position) and remaining measurements at MLP again.
I like Op2 with the modification that no more than one measurement should be done at any one position. Audyssey's precision increases with more data, not duplicates of the same data. To to get more data you have to move the mic, at least a little.

Don't forget, it has to be a ear level, not at seat level. You'll need a tripod.

I agree with Craig.
 

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Discussion Starter #12
The old question related to what Craig is saying is, even if you want to EQ for only one position: Do you keep your head in a vice while listening? And even if you could somehow, your ears are about 6" apart. So, if you measure only one point dead center between your eyes, there may be problems 3" to the left or to the right.
Will it really make any practical difference if one is using only MLP, compared to using three measurement points; MLP, and +/- 3" in relation to that?
 

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Discussion Starter #13
You want to give Audyssey as much information as possible about the acoustics of your room. Therefore, do all available measurements.
What good will that do if one only intends to listen at the MLP anyway?

Then Audyssey will have to do some compromise, trying to get it to some ok at all measurement points, thereby not prioritizing the MLP as much as if that would have been the only measurement point. Or am I missing something here?
 

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Will it really make any practical difference if one is using only MLP, compared to using three measurement points; MLP, and +/- 3" in relation to that?

You asked me if it would make a difference, and you asked Craig if you were missing something. The answer to both those questions is yes! :p

You are equating listening positions with microphone positions during calibration, and they are two entirely different things. Audyssey doesn't care how many listening positions you have. The Audyssey software is based on sampling multiple microphone positions, whether close together for a single listener, or much further apart for multiple listeners, and then correcting for the sampled area. If you are only EQing for a single listener, as I and many others are, then your sampling area can be very small, and your mic. positions can be quite close together. I do about a 22" box with myself at the center, and a couple of measurements very close to my head (just beyond each ear) and about 3" higher. Others use different mic. positions than mine. The key is to experiment to find out what works best for you. But start with the normal protocol of using all 8 mic. positions, in however tight a configuration you prefer. Get a good listening baseline, in accordance with Audyssey recommendations, and then experiment further from there if you wish.

As for whether it really makes a difference to spread your mic. positions at least a few inches out from the side of your head, the answer is probably. If you happen to already have such undistorted sound at your MLP that Audyssey isn't really very necessary anyway, then it probably wouldn't matter much. But the odds of that being the case are really not in your favor, and you would probably need measuring equipment to be entirely sure even then. If you do want to take advantage of Audyssey's room correction capabilities, you need to give it information with which to work. Once you really know what it can do for you and have achieved your best calibration by following the Audyssey instructions, then you can experiment further with fewer mic. positions. But unless you are a very critical listener, you will still probably need measuring equipment to be sure that you are getting better results with fewer than the recommended mic. positions.

Old jokes like: "When all else fails, follow the directions." are funny precisely because it is human nature to want to take shortcuts. But using Audyssey properly is a more complicated process than the AVR makers let on. You will be much better served by starting with the recommended procedures documented in the Set-up Guide and the FAQ, and repeated in this thread. I hope this helps.

Regards,
Mike
 

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What good will that do if one only intends to listen at the MLP anyway?

Then Audyssey will have to do some compromise, trying to get it to some ok at all measurement points, thereby not prioritizing the MLP as much as if that would have been the only measurement point. Or am I missing something here?
Let me repeat what I said:

It doesn't hurt anything, or cost anything except your time to try, so feel free to give it a shot and see if you like it. If not, you can always go back and redo the measurements the *right* way.
That's the only way you'll convince yourself.

Craig
 

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I've had the best results by using only 3 mic positions - MLP, 6" right of MLP, 6" left of MLP.

And, since we're showing off graphs. :)


When you say this Alan do you still use ALL the allotted runs, say 8 but only in those three positions or just 3 tests. I'm assuming all. Or would you do say 32 different tests in only 3 positions
 

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So you have no clue or experience of this, and just say "try measuring at multiple points despite only using the MLP and see it it helps"? :confused:

I'm not Craig (obviously) and I hope he won't mind me answering this, but I consider him to be one of the very most knowledgeable and experienced with respect to this subject. In some ways, his answer was probably the simplest. After everyone has explained why it is important to take measurements at several different positions around the MLP, if you still aren't convinced, then you will probably just have to prove it to yourself by taking just the one measurement to see how you like it. I think everyone has been taking your inquiry seriously, and is genuinely trying to help, as I still am as I type this.
 

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My couch is right up against a cement wall so if I put the mic for the first measurement at my MLP it will only be 20 cm from the wall and close than 1 ft from the seat cushion. If I still do the measurement here and than follow the rule of at least two ft from the wall for the rest at ear level height ( the first reading would be the furthest back) will this mess everything up or is it ok.
 

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I got perfect results using 1 position!:cool:
 
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