Each SM4000 microphone is supplied with its individual calibration data for frequency response and sensitivity. Its modular design allows the preamplifier to be used with any of the high quality BSWA microphone capsules.

SM4201 microphone is top of the line. It is suitable for the most critical recording applications requiring extreme performance and environmental stability. Its nickel alloy construction ensures durability and outstanding performance. The electronic circuitry coupled with a transformerless output stage provides a flat frequency response across the entire audio bandwidth while at the same time achieving an extremely low noise floor.