What music do you use to audition new gear?

Which albums do you use to audition equipment? I have been shopping for new speakers, and I've been thinking a lot about this (and listening a lot).

I want to be clear: I am NOT asking about favorite albums, or about the "best" recordings. I'm curious about the experience of judging components or speakers, which is a very knotty and subjective thing, and which involves both of those factors plus many others. For instance, some people might play, say, heavy metal to test a speaker's crunch and power, even though they listen primarily to soft jazz vocal. Some here will argue one should bring familiar recordings, while others might seek out and bring extremely well recorded material, period (or test tone records!) Others play poorly recorded material, just to see how the speakers reveal it.

To get the ball rolling, here's what I've been bringing with me to hi-fi dealers recently...

-Ockeghem's Requiem --- something beautifully quiet and concentrated----the idea of listening to essentially "one thing," which here is voice... this one probably about soundstage. (Ensemble Organum).
-Kraftwerk, Computer World ---- their production masterpiece. I like to audition something totally synthetic and electronic just to see what the speakers (and my ears) do without any real-world referent.
-Woody Shaw, Cassandranite, 1965 (released 1993 on CD--I listen only to CD) --- an old favorite, thus very familiar. Hard bop, great combo. Classic sound.
-The Pixies, Doolittle --- another old fave, this one with huge dynamic range from song to song: from surging guitar rockers to quieter moans and whispers.

There's so much else, too---but that's the beauty of this hobby!!
I'm eager to hear other people's thoughts or strategies.