Axiom Home Page Forums General Discussion Stereo M50s: what's the extra driver supposed to do?

These should answer your questions and get you started. Calibration is ESSENTIAL to proper use of your system. So, take your time, learn, and give it a shot.

Sound Pressure Level Meter

Avia Guide to Home Theater
Avia: Guide to Home Theater

A Quick Overview of Home Theater Calibration

Setting Speaker Level with AVIA

Well, I'm using my computer to generate test signals, and the SPL meters God gave me, and the results have already been revealing. I'm amazed at how much the sound of pure sine waves is affected by placement.

Avia is a home theater configuration DVD. And Radioshack sells the SPL meters for about $40 or so. If you search around on hre there's a number of threads that discuss Avia vs. other configuration DVDs (they have various test tones and video calibration tools.)

In reply to:

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I'm amazed at how much the sound of pure sine waves is affected by placement.

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Actually, pure sine tones are not the best test tone to use when calibrating your system. Since they are made up of single frequencies, they are highly susceptible to destructive/constructive interferece from room reflections. A broadband test signal like pink noise is much better since it is made up of a broad range of frequencies.

Right, that's why I'm observing such dramatic effects, but I would have thought that you'd want that isolation for calibration...no?

Do you use a variety of frequencies when you calibrate with sine tones? If not, then you're only calibrating for one specific note.

A handful of frequencies, but I haven't done any calibration yet (as though I knew how!), just moved things around a little and marveled at how different it sounds.

Most people don't have multi-thousand-dollar RTAs (Real Time Analyzers)... I find my SPL meter (with the correction table) and a sweep generator (run on each channel independently and then on both) gives me the best results.

Using pink noise to calibrate levels of components such as a subwoofer settings and parametric equalizer frequency, level, and Q settings, would require an RTA. While the results of calibration with this kind of setup are usually more linear than with a simple SPL meter and sweeps, the latter still offers a great performance/price ratio.

Pink and white noise used to calibrate levels between different channels, however, is very useful, and you only need a simple SPL meter to do this.

(moving to a new thread)