The CMC 6 U is designed for standard 48 and 12-Volt phantom powering, its circuitry recognises the supply voltage and adjusts itself automatically and the performance characteristics essentially remain the same either way. The main difference is that the current drawn at 12 Volts is greater than at 48 Volts, however the 12-Volt mode consumes less power and might be more favourable for battery-powered recording applications and scenarios.
The microphone amplifier is responsible for proving the necessary electrical charge to the mic's capsule, without which it would then be unable to generate any signal. Since the capsule’s output signal is very weak (Hi-Z), it must then be amplified in order for it to reach the next stage in the signal chain and must undergo balancing and impedance matching before this transition. The CMC 6 incorporates a balanced, direct-coupled class-A amplifier, yielding a low output impedance, high RF shielding and minimal distortion.
Key Features:
Flat frequency response
Very low harmonic distortion and noise
Works with 12V and 48V phantom power
Balanced, low-impedance output
High suppression of interference on the microphone cable
Excellent protection against high-frequency radio interference with "RFI Shield"
Frequency-independent impedance
Signal transmission possible over very long cables
Reliable operation even with weak phantom power
Symmetrical, transformer- and capacitor-free output stage with a class-A amplifier
Above 20 kHz, the signal is attenuated for protection against interference in the ultrasonic range, e.g. through the ultrasonic autofocus of a film camera
Specifications:
Maximum sound pressure level (THD < 0.5 %): with MK 4: 131 dB-SPL (P48, P12)
Frequency range: 20 Hz - 20 kHz
Sensitivity: see corresponding capsule
Maximum output voltage: 1 V (0 dBV) with 1 kΩ load
Low cut filter: 20 Hz, 12 dB/oct.
Minimum recommended load impedance: 1 kΩ
Output impedance: 42 Ω
Maximum cable length: > 400 m / ~1300ft
SCHOEPS RFI Shield: Yes
Powering standard / Valid range: P48 / 20-52 V | P12 / 10-13 V