Hx100 mk2
IRFP240/9240 Vertical Mosfets
Direct Drive technology

The Hx100 mk2 is a major upgrade. Transistors in the 2nd differential stage have been replaced by 2SD669A and 2SB649A. Coupled with delicate tweaking of component values, the mk2 now boasts lower distortion than her predecessor. At 100W continuous into 8 ohms, THD for 1kHz is an impressive 0.0065%. At 20kHz, it's only 0.0593%. With this level of performance, the Hx100 mk2 is ideally suited for hifi and home theater.

AmpsLab recommends our PSU28K63V for the Hx100mk2. On board are 6 pieces of quality Rubycon capacitors rated at 4,700uF/63V.

Rated Power Output
100 watts continuous into 8 Ω
150 watts continuous into 4 Ω

Input Sensitivty 1.30 Vrms
Input Impedance 33 kΩ unbalanced
Rise Time 2.4 microsec
Voltage Gain 27dB

Power Transformer 40-0-40 Vac (200VA)
PCB Dimensions 120mm x 60mm
PCB Material Fibre Glass FR4
Typical THD @ 100 watts into 8 Ω
1kHz 0.0065 %
10kHz 0.0361 %
20kHz 0.0593 %

Typical THD @ 50 watts into 8 Ω
1kHz 0.0045 %
10kHz 0.0169 %
20kHz 0.0295 %

Measurements made with Boonton 1130 Distortion Analyzer with Signal Generator from a HP339A.

Please note the Hx100mk2 is a discrete amplifier. As such, it is not recommended for beginners.

The Mk2 is one channel and is supplied Unassembled. Two kits are required for stereo.

To complete the amplifier, the following are needed:

1) a power supply - consisting of a power transformer, filter capacitors and a bridge rectifier
2) a heatsink for the power mosfets
3) a metal case and the necessary connectors


2.1 ch Hi-Fi
450W/rms Hx100

courtesy of
Tyler Curran
7-ch Hx100

courtesy of
Daniel Wiering

60 Downes Street | Calais | ME 04619 | USA