Once i upgraded the P1 to a 16 core single crystal copper balanced cable I could use the M11 at the balanced 4.4mm output power is 550mwatts @ 32ohms . Sound was well defined, ample power, but after a rec from BGGAR to pair the M11/w the BA300S tube amp, it simply gave the P1 an extra +3db of oooomph !!! But the tube amp took the great M11 sound, which can be a bit analytical and sterile, to a fuller soundstage and more life-like in person sound. It actually gives the bass light P1 an acceptable well rounded bass, and brings some recessed vocals...