Everybody loves a top-10 list. So, why not a top-50? That’s what NPR Music has come up with—50 of the greatest voices from today and the past—and they are revealing one per week for the rest of the year. The list isn’t all-encompassing, and many of your personal favorites may be missing from the roster. This is intentional—the panel that whittled the thousands of suggestions down to 50 focused on “discovery,” highlighting performers who may be well-known in certain parts of the world or to certain generations but may be new to modern or Western listeners.

Here’s who’s been featured so far: Iggy Pop, Ahmad Zahir, Mahalia Jackson, Maria Callas, and Nusrat Fateh Ali Khan (a TravelTracks favorite). This week we have Asha Bhosle, the great Bollywood singer. You can also listen to a mystery music clip and try to guess who will be featured next week—answer correctly and you could win a NPR Music tote bag. Tune in and enjoy a year of musical discovery!

Want free music? Go to Amazon.com’s MP3 download page. There you will find a free song of the day (like today’s ditty from Butch Walker), and if you scroll down a bit, you’ll see a place to opt in to the Amazon Delivers MP3 Download newsletter. About once a week, you’ll get an email stocked with new music, including 10+ free tracks. Fill your iPod with hot new licks for free!