The harmonics and phase conversion system changes the proportions in the spectrum of harmonic distortion!

A world of music from the comfort of your own home!

"Mr Zdzisław was able to achieve the incredible amplifier – it is beautifully intense, dense, but it does not blend everything into gruel. Its trebles, have exceptional ease in filling the bandwidth without brightening or sibilants. The bass is majestically profound and powerful, although it does not compete with the best with it’s control and selectivity. It creates just a good background and a foundation"


Power amplifier MPA 400 is the next achievement of Struss Audio company. This amplifier is direct response to market requirements for powerful yet detailed and musical power stage.

The MPA400 amplifier is the result of several years of work of the STRUSS AUDIO team. Its construction is based on more than thirty years of experience and knowledge of the designer and owner of Struss Amplifiers, Zdzisław Hrynkiewicz Struss.

After many years of trials and improvements Struss Audio developed spatial system of chassis, where each individual electronic and mechanical component is carefully positioned. This allowed to obtain the shortest possible connections between the elements, high resistance to interference, very good cooling and thermal stability.

Interesting design of the amplifier casing has also been developed.
MPA400 is based on bridge configuration of two monoblocks previously implemented in DM250 integrated amplifier. This together with two 500W transformers in power supply, allows to drive any loudspeaker with low efficiency or so called “difficult” characteristics.
The design underlying the MPA400 was developed in 2000 and has been used in the latest Struss Audio amplifier models, with changes due to new technologies and production requirements.

Unique utilisation of patented topology of electronic circuit allows to achieve very musical and detailed sound with unique holographic detailed sound stage. Also low frequencies are performed with power and excellent control.

MPA400 is good match for every high quality source of audio signal and offers transparency and non-altered audio performance. It can be also interesting option for tube preamplifiers or sound sources, offering exact reproduction of input signal, without any coloration or own timbre. In such case the tube sound characteristics is fully reflected on high power output, with wide frequency range and high dynamic sound.


Nominal output power:
  • 400 W/8 Ω,
  • 700 W/4 Ω
Minimum load impedance: 1 Ω (instantaneous) Recommended loudspeaker impedance: 4 Ω or more, optimal 8 Ω Output impedance: 0,2 Ω Nonlinear distortion – THD:
  • 0.15% at 1 W / 8 Ω,
  • 0.25% at 380 W/8 Ω
Frequency response: 3 Hz – 100 kHz – 3 dB / 1 W / 8 Ω 5 – 50 000 Hz: ± 0,05 dB Frequency response: 5 Hz – 250 kHz – 3 dB / 1 W / 8 Ω Slew rate: 250 V/μs Dynamics: 135 dB Signal – noise ratio: 140 dB (IHF – A) Inputs:
  • RCA/ 47 kΩ/380,0 mV
  • XLR / 22 kΩ/387,5 mV
Power transformers: 2 x toroidal, 500 VA each Filtering capacitors for power supply: 4 x 15,000 uF – Nippon Chemi-Con Advanced output protection system: Against short circuit Against the DC voltage appears on the output Power consumption: 75 VA – 1000 VA (peak) Work in class A: 10 W Net weight: 18 kg Dimensions: 430 x 102 x 338 mm Net weight: 18 kg The amplifier meets the requirements and standards in force in the EU. Manufacturer’s warranty: 24 months

Remote Control: code RC5 (volume)