http://www.hometheaterhifi.com/volume_10_2/outlaw-audio-200-amplifier-4-2003.html:

"The frequency response is the only area I see room for improvement. It starts rolling off about 3 kHz, although it is down only 0.3 db at 20 kHz. The low end though suffers a bit, dropping 1 dB at 20 Hz. Perhaps this is an overzealous use of an input capacitor (these are commonly used to prevent DC from getting into the power amplifier from the preamplifier). I would suggest using a higher value to keep it reasonably flat to 20 Hz. It is not so much that you can't boost the low end with a tone control somewhere, but there is phase shift where you have frequency response rolloff."

The rolloff is not as bad as I remember, though: it's down only 0.3 dB at 20 Khz -- arguably inaudable. I had thought it was 3 dB down.

Still, when an Odyssey Stratus Plus sports 2 Hz to 400 kHz +0-1dB (admittedly, a $1200 amp - not cheap, but not uberexpensive, either), one has to wonder why the M200 isn't flatter. Most of the expense of the Stratos is due to the fact that it's an over-built 160 wpc class A/AB amp. (Class A to about 5 W).