they're all cool. If you want a copy of the 2nd one, I can sell it to you for $10 shipped. It's unopened, I have an extra one. Email me back and I can list the contents. cheers
Both, they have tones at different frequencies which can be used in concert with a Sound Pressure Level meter to measure your speakers performance and tweak placement as well as such tracks to balance the levels between the channels and a track designed for burn in. There are also musical tracks to use for testing the quality of the sound.