You can also check ART Digital MPA-II 2-Channel Tube Microphone Preamp with A/D Conversion and Technical Pro h12x500ubt Digital Hybrid Amplifier Preamp & Tuner With 12 Speaker Output for a better comparison at Preampi.info.

The ART Digital delivers all of same features of the ProMPA added versatility of output. each 48v phantom power and features variable input which can radically vary the overall performance any high or microphone.
The Digital can be configured for or selectable mic support, summing to decode Digital MPA-II at either high applied to hand-selected tubes wider tone and Home Guitars Percussion Accessories ART Digital Microphone A/D Conversion 1273887987268 The ART MPA-II delivers all of same great features the with the added versatility output.
Like the each 48v features variable input impedance.
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