I finally purchased a Matrix M-stage to go with my Q-701. I connect my iphone to it via a 3.5mm to RCA, and the sound quality is very dissapointing, not even as good as directly using iphone's headphone jack. The sound stage is much improved, but the sound is not clear, quite distant, and resolution is reduced, and noise floor is quite high. Does anyone have experience with iphone directly to M-stage? Is this expected, or my M-stage might be defective? Do I need an external DAC or good CD player to really make the M-stage work? I read that K701 is great with M-stage, but how about Q701? 1) I ordered a 110V M-stage, and the correct model arrived, but the power cord included in the box says "250V 10A". I used a spare computer monitor's "110V 10A" power cord instead. Could this be a problem? 2) This is my very first headphone amp, so i have no reference to compare with. However, when I set gain to 20dB, and turning M-stage volume all the way up, and iphone volume all the way up, it seems that the sound is not un-bearably loud, and not much louder than using iphone's headphone jack alone. Is this strange? I expect M-stage to significantly boost the volume, offering decent volume when both iphone and amp's volume are around mid-point, but that doesn't seem to be the case. Both iphone and M-stage have to be turned up almost to maximum... 3) When I hook my PS3 to M-stage, and turn up the volume nob without playing anything, the noise floor is very noticeable. I assume it's caused by PS3 not M-stage, since it's quite if I do not input any source to M-stage. The sound quality with PS3 is bad, too, and I'm not sure if it's due to PS3's internal DAC, or M-stage. When I use PS3's internal DAC and A/V receiver, the loud speakers sound fine. 4) When I connect iphone to M-stage, the noise found in PS3 is gone, but when I play music, the background noise in the recording is much more noticeable. I primarily listen to classical music, and many recordings are from the 60's, so noise in recording is kind of expected, but it is much more noticeable through M-stage+Q701 than just iphone+Q701, or through the loud front speakers. Is it because M-stage unveils more "details" in the recording? Is there a way to resolve this issue? As a newbie to the hobby, I would really appreciate your patience and help! Many thanks!