You should look for songs you are familiar with. Most of the modern recordings are of good quality. Always carry CDs.
Jagjit Singh's Journey is a good 2 CD album with most of his famous songs. Most of the Safar albums (Kishore Kumar, Rajesh Khanna, Mukesh) are all good. Look for songs by Shankar Ehsann Loy as they use a lot of instruments and usually push the amp/speaker combination quite hard.
In non-filmi, I consider 'Breathless' by Shankar Mahadevan to be one of the best albums for testing.
Cheers
Folks,
Do try Lucky Ali's albums, Sifar, Sunoh. They contain rare instruments and sound very different to regular Hindi movies. I take them for auditions.
Cheers