Sennheisere 901
microphone
New retail price (MSRP)
$279
Used market: $220*
Specifications
2 of 8 values have a recorded source- Connectors
- XLR 3-Pin Male·
- Built-in converter
- no·
- Transducer
- Condenser Electret·
- Sensitivity
- -66✓
- Output impedance
- 50·
- Phantom power required
- yes·
- Connection
- XLR-Only·
- Indexable Locales
- ·
Expert Audio Engineering Commentary
Tonal profile
A half-cardioid boundary condenser that lies on a cushion inside the kick drum instead of being aimed at it. The half-cardioid pattern is what a cardioid becomes when it sits on a surface: no rear pickup and 6 dB of pressure gain from the boundary.
Gain staging
-66 dBV/Pa (0.5 mV/Pa) is quiet for a condenser and normal for a boundary microphone built for 130 dB inside a drum shell. Phantom is mandatory - it is P48, and the sheet says so plainly.
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.
«Nominal impedance 50 Ω»
The specification table gives 50 ohms as a value. The Architect's Specification paragraph on the same page says 'Nominal impedance shall be less than 50 Ω'. A value and an upper bound are not the same statement: the second says the real figure is unknown and below 50, the first says it is 50. The practical consequence is small at this impedance, but the pattern matters - the same sheet layout is used across the whole e 900 range.
checked 8/6/2026* Estimated with the depreciation fallback (~79% retained value).