MOS-101S Stereo amplifier, the musical amplifier

The MOS-101 was designed foremost with the emotional experience of music listening in mind. The MOS-101 is an class-A amplifier with an open loop MOSFET output system and pacified high frequency driver system for ultra smooth sound.

he output stage, with open loop MOSFET design, works in Class-A most of the time for ultra transparent sound. - See more at:

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 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.


  • Stereo end-amplifier with high bias MOSFET output
  • Power 2x 40W in 8 Ohm, 2x 60W in 4 Ohm
  • Total harmonic distortion below 0.1%
  • Open loop output stage, ultra stabile design without output coils etc.
  • High peak current reserve, keeps control over difficult to drive speakers
  • Bandwidth above 200 kHz, excelled match for high-resolution sound
  • Noise cancellation inputs with discrete JFET input circuit design
  • Precision machined sturdy metal case, no vibrations

Applications & Specifications

Detailed technical specification:

Core specs

  • Stereo end-amplifier with dual 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 (10x)
  • Noise & hum better than -90dB
  • Max power 2x 40W in 8 Ohm, 2x 60W in 4 Ohm (20Hz – 20kHz, THD <1%)
  • Total harmonic distortion till 8W (20Hz-20kHz in 8 Ohm): <0.02%
  • Open loop output stage, high bandwidth ultra-stabile design without output coil.
  • Frequency range 5 Hz till 300k (-3dB @ 8W 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, matched MOSFETs, Toroid transformer, 2 oz, 2 layer  PCB board.


  • Speakers, 4 way binding posts, left and right


  • Cinch inputs with ground loop hum cancel circuit


  • Power on/off switch
  • Environment: relative humidity 10 – 90% non-condensing, temperature limits:  10C– 45C operating, -20C to 80C storage.
  • Net weight: 9.0 kg, gross  weight: 12kg
  • Dimensions: 300 x 100 x 320 mm (excluding protrusions)
  • Power supply: maximum 300W, 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 cinch connectors are available.