Discover model DMI 3H

Dual mono integrated hybrid amplifier



This Audio Alto’s compact series reflects maximum effort and knowledge, as it presents quite a different solution with its built-in electronic tubes as voltage amplifiers. Result of design and construction is its acoustic-inertial and elegant shape.

The AA DMI 3H is designed as dual mono amplifier and with modularly design enables an insertion of different input modules (Phono RIAA MM/MC etc). AA DMI 3H power supply is realized with two 150VA toroid transformer with a electrostatic and magnetic screen that provides with also doubled electronic regulators power to each set of the amplifier individually. Heating of electronic tubes is regulated and is time-controlled for optimum operation and for achieving their life expectancy of over 5.000 hours. Power supply voltage for tubes is time delayed and regulated.


AA DMI 3H is handmade and all components are tested prior to installation.

A complementary MOSFET output transistor transforms the CCDA output with output impedance of few hundreds of ohms to low impedance (high current) output required by speakers. The output transistors are biased with an innovative dedicated circuit that keeps both output transistors biased during the whole signal phase (360°) reducing the low power related distortions (no typical class A/B turn off/on that is the cause of unpleasing crossover distortion).The circuit significantly reduces the distortion caused by the effects of nonlinear transconductance in the output transistors resulting in a sound identical as it would be produced with an pure class A output stage.

The voltage and current amplifiers work without any global negative feedback!

  • Inputs

    I2 – RCA 220Kohm, 500 mVeff sensitivity (line input), Noise -95dB
    I3 – RCA 220Kohm, 200 mVeff sensitivity (line input), Noise -95dB
    Tape in – RCA 220Kohm, 200 mVeff sensitivity (line input), Noise -95dB

  • Output

    Tape out – RCA, 200 mVeff
    Headphone – 0.9 Veff @ 32 Ohms
    7,5Veff @ 600 Ohms
    4 x Speakers posts 4 mm

  • Gain

    30 dB (70 dB Phono MM)

  • Output Power

    Model A: 2 x 30W @ 8 Ohm, 2 x 50W @ 4 Ohm

    Model B: 2 x 60W @ 8 Ohm, 2 x 100W @ 4 Ohm

  • Frequency response

    5Hz to 60.000Hz -1dB

  • Vaccum tubes

    2 x 6922 (E88CC or NOS 6DJ8)

  • Dimensions

    (W x D x H) 295 x 465 x 93 mm

  • Weight

    12.5 Kg

  • Finish

    Dark Shadow, Silver, Inox, Chrome, natural solid wood (i.e. walnut)
    or upon special order in various colors