How tough is it to calibrate using SPL meter and Avia? (1 Viewer)

[Marc Go]

I am relatively new to HT and have an Onkyo 595 with the Poly RM6600 surrounds and Polk 350 sub. The system sounds terrific like it is, but everyone I talk to recommends getting a Radio Shack SPL meter and Avia Guide to Home Theater. Both seem relatively inexpensive for assuring that my HT sounds (and looks) its best! Any tips on using this for a newbie? Is it relatively straight forward and explained clearly on the DVD? Any help would be most appreciated. Thanks.

 

[Bryan Acevedo]

In my opinion - the Radio Shack SPL Meter is a must have. Avia is not as critical, as your receiver has internal test tones that you can use. Saying that, I have both, and Avia is a great resource, but not needed to do basic calibration.

It is very easy to do with an SPL Meter and your receiver's internal test tones. Here are the steps:

1) Set your SPL Meter to either the 80 or 70 mark, slow, and C weighting.

2) Go into your receivers test tones and start playing them through the front left channel. Turn up the volume on the receiver until the front left channel reads 75 db on your spl meter. If you set your meter to 70, then it will be at the +5 setting. If you set your meter to 80, then it will be at the -5 setting. Some have said the meter is more accurate setting it to 80 and reading down. This is how I have done it, with great results.

3) Now, without adjusting the main volume, select the tones to play out of your center channel and adjust that to 75 db using that channels level control. Do this for all of your speakers (and your sub).

A few of problems you may have:

- I have no idea if Onkyo lets you adjust each speaker separately, or only with its other speaker in that pair (i.e. both rear speakers). This may make one speaker louder than the other if they are not the same distance from you.

- The sub level is usually kind of tricky. If you have room interaction, you may have to adjust the sub too low to get it at 75 db. Most people here adjust by ear after doing a basic calibration.

- My Denon adjusts the volume to 0, and lets you adjust each channel independently, but your Onkyo may do it differently. So some of this may be slightly different.

What Avia gives you on top of this are different test tones to find phasing problems, crossover problems, etc., and video calibration tools. It is very helpful! The difference is that in Avia, you do the same calibrations to 85 db instead of 75 db. It may be hard, because on some receivers, you can only set the levels when in its own test tone mode. So you can't adjust based on the Avia tones.

What some will tell you, is that Avia is more accurate, and that the Onkyos aren't. I think most people have problems, because they try to adjust the internal test tones to 85 db, which is incorrect. As far as I understand it, Dolby requires all internal test tones to be calibrated to 75 db. That is their standard to have the Dolby license. On my system, when calibrated, I get 75 db with internal test tones, and 85 db with Avia - without readjusting anything. So it works exactly like it should.

Hope this helps.

Bryan

 

[Pete Mazz]

Don't some Onkyos have internal sub tones that are 10 dB too low? Do a search. I remember reading something like that.

Pete