MOS-201S Stereo amplifier, the Smart musical amplifier

The MOS-201S is similar to the MOS-101 but is more powerful for use in bigger rooms and has a smart display showing the health of the amplifier for peace of mind.

The output stage, with open loop MOSFET design, works in Class-A for ultra transparent sound. When you're in the mood for background music only, the bias can be switched to Class-AB for 50% power savings.

Be prepared for a whole new level of emotion! The sound has an analogue, smooth feeling to it with no sign of harshness. High tones sound delicate and precise. Music comes to life as if the fog was lifted.

This product is no longer available. This product is replaced by the 'Natural Phase' platform which is available through our Audio Full Custom Build department.

Applications & Specifications

Detailed technical specification:

Core specs

  • Stereo end-amplifier with 3 pairs of MOSFET output
  • Class-A operation till 25W peak into 8 ohm.
  • Input sensitivity 2V RMS for maximum output power
  • Closed loop gain of 20dB
  • Noise & hum better than -90dB
  • Max power 2x 40W in 8 Ohm, 2x 65W in 4 Ohm (20Hz – 20kHz, THD <0.1%)
  • Total harmonic distortion at 0.1  till 8W (20Hz-20kHz in 8 Ohm): <0.02%
  • Open loop output stage, ultra stabile design without the use of output coils etc.
  • Frequency range 5 Hz till 300k (-3dB @ 1W in 8 Ohm)
  • Damping factor 40
  • High peak current reserve of 20Amps, keeps control over difficult to drive speakers
  • Minimalist approach to circuit design to retail the finest music details
  • Component technology:  Matched JFET pair input stage, output matched dual pair vertical MOSFETs, Toroid transformer, 2 layer PCB board, temperature monitor & control circuit


-          Speakers, 4 way binding posts, left and right


-          XLR balanced inputs

-          Cinch inputs



-          Power on/off switch

-          Remote control

-          Environment: relative humidity 10 – 90% non-condensing, temperature limits:  10C– 45C operating, -20C to 80C storage.

-          Net weight: 10kg, gross  weight: 13kg

-          Dimensions: 300 x 100 x 320 mm (excluding feet)

-          Power supply: maximum 250VA, available in 115 VAC and 230 VAC models

-          Power cord included

-          Designed in Europe

What can this product do for you?

Upgrade existing system:  connect the amplifier to the preamp-out of your existing home theater receiver to experience a new level of stereo listening. Requires an extra pair of loudspeakers or speaker switch.

Combine with Cyenne Audio DAC:  The 5 and the 3 series of DAC can be directly connected to the power amplifier for the best possible sound. No need for pre-amp.

To replace existing end-amplifier:  Is easy as both XLR and cinch connectors are available.