Axiom Home Page Forums General Discussion Home Theater Balancing speakers with SPL meter and Avia disk

Ok first question, I just read the directions to the Radio Shack sound meter and it says to point the meter at the speaker. Then I just watched the Avia directions on how to use the sound meter. First the say the analog one is better than the digital one but I bought the digital then they say to point it at the ceiling when measuring? So which is right? At the speaker or at the ceiling?

Next question I first calibrated using the receivers test tones which were at 75db which is what I want. But I had to do a different adjustment on all the speakers? I pointed the meter at each speaker and here are the results:

FL 1.5
C -2.0
FR 0.0
SR-1.5
SL-0.5

Now does this look right? Granted the left side of the room is open to a about 3 more foot of space going to bedrooms and a stairway. The room is 11x17x10 with the fronts on the long wall.

My setup is M3 fronts vp100 center and QS8 rears. I don't have my subwoofer yet. I'm using a denon 3803. I tried to used my dvd players(rp91) test tones(in the menu) but no sound? The Avia tones worked but I didn't adjust anything with them. Thanks for any help and advice in advance!

I wouldn't worry too much about the numbers as long as they sound even to your ears, too.

I don't have the digital meter, so I can't tell you which is the correct way to point it. With the analog meter, in addition to pointing the mic at the speaker, you also have to make sure you're not directly behind the mic as it may skew the readings.

I know sushi has a digital meter. He may chime in and help you out.

You should also try adjusting using the Avia test tones (at 85db), your results may be different. I have also noticed a difference between different setup discs as well. For instance VE always ends up being about 3-4 db higher in volume than with Avia, but with each individual speaker at the same calibration level. Just about every speaker manufacturer suggests calibrating with the meter pointed up, but try it both ways. I doubt there will be little if any difference at all.

Thanks for the responses. I'm still confused though. There's a difference in the db reading when pointing at the ceiling instead of the speaker(significantly less db). Second should I be using the receivers pink noise or the avia disks pink poise. Reguardless I want to use 75db not 85db as my listening level.

Another question if any of you have an RP91 dvd player how do you channel balance with it. It has a test but no sound comes out. I'm using the coxial digital out and I don't know if that makes a difference.

So 3 main questions,

1. Meter pointed at ceiling or speaker?
2. Calibrate using receiver or DVD player or Avia disk?
3. Why isn't the DVD player's channel level test working(no sound when in test)

Thanks for any further advice you can provide.

You'll want to use the tones from the Avia disc. Also it's probably wise to go ahead and calibrate at 85db, and then check it at 75db to see if there are any changes. There may be, and maybe not. Even if you do not plan to listen at the 85db reference point, once you get your speakers properly calibrated at the 85db level than all you would have to do is just run the tones and lower the volume until you reach the 75db mark.

Thanks for the fast reply but I don't understand the logic in balancing at 85db if I plan on listening to them at 75db. The Avia disk states to balance according to your preferred listening level and that 75db is more the standard in home application vs the 85db reference which most say is too loud for home use. I mean if I calibrate at 85db then lower to 75db and they aren't balanced I'm going to have to re-adjust them again right?

Would anyone else care to explain the reasoning behind it? Or tell me why using the Avia disk pink noise over the receivers pink noise is better or even the dvd players own pink noise? Thanks for anymore more input on the subject!

The logic behind using the Avia disc, as opposed to the built-in test tones, is that tones originating from a disc in your player will travel the exact same electronic pathway as the signals to which you will actually be listening in the end: i.e., CDs and DVDs. In my own experience, I found there to be a significant difference between the settings generated by Avia and those generated by my receiver's test tones. I did, however, use my player's test tones to balance my DVD-A/SACD analog-out settings, since I don't have a 6-analog-channel-out test disc. Does anyone know if such a thing exists yet?

I share your curiousity about the "reference level" question. Any takers?

I didn't see it posted but you don't should have the meter facing the ceiling or the ceiling where it meets the front wall. You don't point your ears at each speaker when listening to a movie. Your head is generally in one place (center of the room facing the TV). So the meter is acting as your head in listening position.

Frank

Interesting Rob, I can see the logic in using the Avia disk to balance due to the fact it will be the source I watch DVD's on. But since I'm making the changes at the receiver level won't it affect all the sources on the receiver? ie. satellite tv and xbox?

I figured the best way would to be able to use the channel levels in the dvd player menu that way I'm only affecting that source. I don't think I can channel balance each source at the receiver's OSD menu.

So say I channel balance with Avia disk pink noise and watch a movie and it's perfectly balanced. Then I switch over to Satellite to watch a movie in Dolby Digital and it's not balanced. Since it's a different source wouldn't this cause a problem for channel balancing? This is why I was thinking using the pink noise of the receiver to channel balance would balance all the sources out(more evenly?). Thoughts?

A few thoughts:

(1) Balance using each possibility (e.g., receiver test tones, player test tones, Avia test tones), and write down the results. If the differences are not significant (say, less than 1 dB), then you don't really need to choose.

(2) If there is a significant difference, then you can either (a) split the difference for the affected speaker(s) or (b) use the settings most appropriate for the source whose audio quality you value most. I used the latter approach, but then I don't watch much TV and our radio reception is nonexistent.

Good luck!