Low power system based on the efficiency of the ZUs, the 9 watts of the SE9 are more than enough in this room. I have not had a chance to do serious listening since setting up the Omens, first impressions are positive. Plenty of bass which was one of my main concerns. Still awaiting the arrival of the NFB-11, for now using the audio out of the airport express. I went with the NFB-11 due to its use of the ESS Sabre 9018 chip, this should improve the resolution substantially over the jitter prone audio out of the AE. Music can be streamed to both systems simultaniously, the difference between the two is quite dramatic to say the least.