Ellen- The Chesky disc is really useful. 1st, it has 9 music selections in DVD-V and DVD-A format. (Stereo and multichannel.) You can set levels, DVD-V and DVD-A. Also, phase check between all speakers, and phase checks to the sub, again, all DVD-V and DVD-A. There are also "impulse" type tests, used to make sure all the delays to your speakers are correct. And this I thought was really unique: it has a low freq pan through all the mains. The idea is that if your BM is functioning correctly, even though the low freq pan is *only* through the mains, the output to the sub should remain constant. (There is a little beep as each pan "centers" on each main speaker.)

I had always used Avia as my bible for audio setup, but the Chesky disc gives it a run for the money IMO. (No video setup stuff on Chesky though.)