The bass is a little thicker, and over all a little more refined... However to be honest I have not had enough time with the few I have. The batteries will last forever on one charge so your probably loose your charger I think before you actually need to use it. We did not make any drastic changes to the Rx sound because we felt that the "sound" was not broke and did not need changing much. The main improvement was the battery enlargement, hi lo gain switch, better in and out jacks and the size pairing to match the AlgoRhythm Solo.