HE-150/150M MOSFET Power Amplifier

Ultra Linear High Current Circuitry MOSFET ZERO feedback design
Designed over a lifetime and Hand-Made by Peter Ledermann

The HE-150 amplifier's design is the  result of nearly 40 years of research in solid state amplifiers with the goal of building the most transparent and most reliable design possible. Years of investigation into why most solid state amplifiers cause listening fatigue and often cannot be listened to at all power levels has yielded tremendous results - a highly linearized, Zero Feedback lateral MOSFET amplifier ~one that has been called the most fatigue free sounding, tube like circuit ever made. Although it has the warmth associated with tube designs, it also has (unlike tubes) ultra low distortion and is free of the colorations that tube amplifiers cannot avoid. Being solid state, it does not degrade over the years requiring constant expensive feeding of new tubes and other components due to heat damage. It is unique in the industry, and always solicits comments about how it "disappears".....after all, an amplifier should not get in the way or be noticed....  except for its absence in interfering with your listening.

200 W/Ch. into 8 ohms/265 W/Ch @ 4 ohms
HE-150 features “Vary-Light” Power Level indication
HE-150M Features "V" display power level indication
Clipping indication for each channel
Touch switch for muting
Touch switch for making Vary Light feature steady light
State settings (power/mute) remembered during mains power off to unit
All models feature unbalanced Inputs; Amplifiers are single ended, non-bridged Output designs (Balanced input &/or bridged output designs are available)

10 year warranty


Power requirements: 115 V+/- 10%, 50 - 60 Hz, or 230V +/- 10%, 50-60 Hz

Power consumption: 50 - 770 W

Dimensions: Width: 15.75” Depth: 17” Height: 4” Weight: 46 lbs

Continuous Average Power Output (per/ch): 8 ohms, 20 - 20,000 Hz 200 watts,

THD < 0.021 %, @190 W/channel

Frequency range: +0/- 0.1 dB, 20 - 20,000 Hz

Output Impedance (20 - 20,000 Hz): typical 0.04 ohms

Wideband Damping Factor: typical 200

SMPTE Intermodulation Distortion: typical 0.05 % IHF Intermodulation Distortion:typical 0.05 %

Slew Rate: 250 V/µS

Channel Separation: > 75 dB

Continuous Average Power Output into 4 ohms (per/ch): 225 W

Frequency range @ 1 Watt: +0/- 0.2dB, 0.1 Hz -1.5 MHz Sensitivity (1 W/8 ohms/1 kHz):800 mV

A-weighted Signal-to-Noise ratio: (Ref. 1 W/8 ohms) 99 dB Minimum

Pulse power: 1250 W in 0.5 ohms


    width height depth   weight
Product Name inches cm. inches cm. inches cm.   lbs. kg.
HS-150/150M 15.750 40.005 4.125 10.478 16.500 41.910   37.00 16.78
IN SHIPPING BOX 33.500 85.090 9.500 24.130 20.250 51.435   47.00 21.32

They Said What?

" ... it's not even close, as I've never heard any other phono cartridge deliver this type of monstrous sound and flat frequency response without having at least some distracting artifacts. Perhaps the music was simply too engrossing to be able to pin down anything other than the music being reproduced with such a connection to the source. The delivery system seemed to disappear, leaving only music."

- Tom Lyle, Enjoy The Music .com

About These Products:

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