Marten M-Amp Monoblock Power Amp

Swedish Marten is well known for high-end speakers—I profiled the incredible Coltrane Supreme last June. But the company introduced something different at CES 2011—its first power amplifier, the M-Amp monoblock.

The fully balanced M-Amp is based on Marten's proprietary Adaptive Modulation Servo (AMS) technology, which is described as an "inverting, globally self-oscillating, class-D stage" as well as a "load-independent, wide-bandwidth, first-order modulator, switching at 600kHz, with a constant loop gain of 30dB all the way up to the switching frequency." That's more than a mouthful, but the result is hard to argue with—a maximum power output of 550 watts into 8Ω, 1000W into 4Ω, and 1700W into 2Ω with 1% THD. Even more impressive, the THD at 400W into 8Ω is only 0.05%, and it's even less at lower power levels. In the audio band from 20Hz to 20kHz, the output is flat with a tolerance of +0/-0.05dB, and it's only +0/-3dB from DC to 120kHz.

And the price? $45,000/pair. I didn't hear the M-Amp at CES, but Stereophile's Erick Lichte did, saying in his report, "The M Amps never let on that they were class-D amps, sounding more like super powerful tubes or a richly voiced class-A amp."