SCA S90 Series Microphone Preamp Module
The Seventh Circle Audio S90 is a transformerless microphone preamplifier that delivers the unmistakable character of the popular SSL 9000 consoles. Instead of the gain trim knob, the S90 features a switchable High-pass filter going from OFF-220 Hz using a 12 position Grayhill switch. Available as a DIY kit or fully assembled mic preamp module.
The S90 delivers up to 70dB of gain. This is more than enough gain for most applications, especially with modern high-output condenser microphones.
Stepped Gain Control
A 12 position Grayhill switch provides accurate and repeatable gain settings in about 5dB steps from 15dB to 70dB.
Inverts the signal phase.
Slow-rise phantom power minimizes pops and thumps.
Switchable from OFF-220 Hz using a 12 position Grayhill switch provides accurate and repeatable filter settings
High quality PC mount connectors eliminate cabling and ease assembly.
Polypropylene Coupling Capacitors
Instead of an input transformer, the S90 uses a combination of high-quality polypropylene film capacitors and bipolar electrolytic caps to block +48V phantom power while maintaining flat frequency response to below 10Hz.