Pro MPA II
intermediate
$309
Used market: $255*
Specifications
3 of 7 values have a recorded source- Type
- outboard_preamp·
- Added Gain dB
- 75✓
- Input Connector
- 2x 3-Pin XLR Mic (150-3000 Ω adjustable) + 2x 1/4" TS Instrument (>800 kΩ)·
- Output Connector
- 2x 3-Pin XLR + 2x 1/4" Line·
- Expert Description
- En: Two-channel valve preamp with continuously variable input impedance from 150 to 3000 Ω and a switchable plate voltage: at normal plate voltage the response runs 15 Hz to 48 kHz, at high plate voltage 15 Hz to 120 kHz. Maximum gain 75 dB, maximum input +19 dBu, maximum output +27 dBu on XLR. · Uk: Двоканальний ламповий преамп із плавно змінним вхідним опором 150–3000 Ω і перемиканням анодної напруги: за нормальної смуга 15 Гц – 48 кГц, за високої — 15 Гц – 120 кГц. Максимальне підсилення 75 дБ, максимальний вхід +19 dBu, максимальний вихід +27 dBu по XLR.·
- Provides Phantom Power
- yes✓
- Requires Phantom Power
- no✓
Expert Audio Engineering Commentary
Gain Staging Advice
The plate voltage switch is the real character control: high plate voltage means more headroom and a cleaner, wider response, low plate voltage means the tube colours earlier. Neither changes the gain figure.
Production Warning
Variable input impedance down to 150 Ω loads a ribbon heavily. That is a tonal choice, not a fault, but it also changes the microphone's effective output level, so re-check gain after every impedance move.
What the datasheet actually says
Quoted verbatim from the manufacturer’s own page, with the date we checked it. We state what is printed, not what anyone intended by it.
««Equivalent Input Noise: 129dBu (XLR, "A" Weighted)»»
ART print this preamp's equivalent input noise without a minus sign, while their own pages for the TPS II and the Tube MP print the same quantity as "-129dBu (A weighted)". As printed here the figure states 129 dBu of noise at the input, which is not a physical value for a microphone preamp; the intended reading is -129 dBu.
checked 8/5/2026* Estimated with the depreciation fallback (~83% retained value). · checked on 8/5/2026