Songs you use when auditioning gear

Ma recordings.

Chesky recordings.

Blue Coast recordings.

I haven't auditioned gear for quite a while, but if I was going to I'd probably use the Cowboy Junkies cover of Sweet Jane off the Analogue Productions SACD.  I have a couple of Patricia Barber Cafe Blue SACDs and I'd probably use assorted tracks from one of them.

Dorati 1812 Overture on Mercury Living Presence especially the final movement where all heck breaks out. 

Jerry Mulligan - Dragon Fly - track two - Brother Blues

Tom Scott - Smokin Section - track 5 - Ode to Billie Joe (yes that song)

Miles Davis - In a Silent Way - Side 1

Al Di Meola - The Infinite Desire - Track 6 - Invention of The Monsters and Track 10 - Race With The Devil on Turkish Highway

These tracks will show everything a system has to offer. IMHO

I use difficult music such as Sarah McCoy's "Blood Siren." It's a mysterious and unorthodox album that I love. McCoy has a speech impediment and a cajun accent to boot. When I ran it through recently acquired Audion mk3 monoblocs it was when I was hearing lyrics previously unintelligible that I knew it was broken in and measuring up to the hype.

Also, "Harrow and Harvest" by Gillian Welch. Her voice can be treble sibilant and irritating in a lesser system. Th Audions tamed it without killing any detail.

Also, James Taylor's "October Road." Taylor's voice can be honky in less refined systems. A grown system tames the honk while preserving all the details of this masterful recording.

Also, Leonard Cohen's album "You Want It Darker." In an immature system Cohen's voice can be unctuous and gravelly. In a mature system all of that disappears, and his voice becomes a fine instrument floating in a bath of fine instrumental balance and angelic chorus.

On all of these albums if the midrange is not engaging then the emotive power of the human voice is absent as well.