boss303Boss SP-303 Dr. Sample - See the best prices from $563.66, read 7 real reviews, discover how 34 pro artists use it, and see photos of it in actual setups.Discontinued. The BOSS SP-303 Dr. Sample offers DJs and musicians a compact, easy-to-use portable phrase sampler with CD-quality sound, 8-note polyphony, 26 onboard effects and a