What are your go to LP's for evaluating new gear or new tubes?

@dogberry 

Thanks to you. I'll probably pick up more. 

Doors Strange.Days lp , 45 rpm.

@richardbrand 

I did some research on these pianos. There are some youtube videos. Bosendorfer also makes a couple of models with extra keys. One has 97 and the other maybe 93? Can't remember. The lowest notes sound strange but it is just YT video. Going to start another thread about the notes below 20hz.

I forgot about this one:

Jan Hammer - “First Seven Days”. Especially the first track “ Darkness, Earth in Search of the Sun”.  Lots of low notes and great dynamic range.

When I make changes to the system I just play all the music I love to listen to, and much of it isn't boutique audiophile reissues or anything like that. A lot of it is jazz and classical and early music records from the 70s I have listened to for decades. Some of it is more recent reissues (Tone Poets, AP reissues, etc) that I also pull out.