I owned the MA900 and have recently heard the 1R. Wasn't a super big fan of the 1R. Loved the design of it, but the sound was very bassy, with a very unnatural sounding mid bass hump that really hollowed out the midrange and made it feel thin. The MA900 had a much fuller and warmer midrange that really sounded nice. I agree with others that the design of the MA900 just didn't do the sound justice.