Test CD s, which ones to get.

Does anyone know of which test cd's work the best or were to get them? And is there any good place to go to get good instructions on how to use them. Thanx for your help.
The best test discs imho are;
- PAD Luminist system enhancer cd
- Isotek Ultimate system setup disc
- Granite Audio Ultimate low bass test cd (particularly useful to dialing in subs).
All the above cd's work well & are safe to use if the instructions and common sense are followed.

Depends on what you’re trying to do. For setting up speakers the best is the XLO Test CD, using the track with Out of Phase info. "Listen to my voice. It should be coming at you from all around the room." When you get the best non-coherent surround sound effect after experimenting with speaker location as well as room tuning devices from the Out of Phase track you’ll get the best coherent stereo from tracks on CDs that are In Phase, which as fate would have it are not that abundant. May the force be with you. 😳

As we start 2017 I am still looking for the Dali Vol.1 test CD.
Also looking for the Rives Audio 1or2- test cd.