That depends on the earphones you are using, the r5 is has more bass, but in general the sound on the SR15 is more detailed, including bass. I prefer the bass of the SR15, but not by far. For the flexibility of use, and being not so much bigger than the SR15, for daily, use I prefer the R5, but when I sit to listen music at home, the SR15 is my choice. If you use erarphones like the E5000 or the Campfire Comet, there is not so big difference in sound, but with earphones like the K3003, the Xelento or the W80, the SR15 sounds better. For daily use I usualy match the R5 with the Comet, and although not so detailed, the sound is very nice.