Mezzoforte is born in need of conjuring up the emotional charge of the music in the technically most rational way, in the same size as the Soltanus Acoustics Electrostatic Headphone Driver Unit.

Why Hybrid topology?

Considering the technical background of the amplifier designing, and audiophile requirements, the voltage gain had been realized with the popular ECC82 double triode in harmonic interaction with hand-wounded, wide-bandwidth output audio transformers.
The tube can be replaced by any substitution of the ECC82, even with the best vintage ones, without any need for tunning the unit.
You don’t need a matched pair of tubes, because the Mezzoforte uses only one piece of tube.
The adequate current is delivered by precise operational amplifiers. The amplifier has a short circuit and over-temperature protection.

In this combination, Mezzoforte is capable to drive simultaneously two electrostatic headphones and one dynamic or planar headphone.
The stable and powerful operation is allowed by a double-filtered power supply in capacitance multiplier topology.Our Audio step-up transformers are wounded by hand to ensure the highest quality in the high-frequency range and use extremely oversized cross-section cores, which enables high impedance and outstanding low-frequency reproduction.
The housing is made from solid 6mm and 3mm aluminium alloy sheets, preventing vibrations or generating any eddy currents by transformers.
The housing can be used vertically, to use it as a headphone stand, and horizontally too, as usual.


Vacuum Tubes That Can Be Used

ECC82, 12AU7, 6AU6, 12AY7, 13D8, 6AU6, 6GU7 or 6072, 6CC40

Frequency response

hybrid amplifier: 0-100KHz (-3 dB)

Frequency response audio transformers

4-60KHz (-3dB)

Amplifier level input

12V RMS/600V RMS output

Input impedance line level


Input impedance amplifier level

100Ohms nominal

Number of inputs

2 x RCA, 1 x Amplifier level binding posts

Maximum output voltage

700V RMS

Standard bias voltage

580V DC

Power voltage

115 or 230V AC