The Studio Electronics Boomstar SE88 is a CS-80 style filter for use in Eurorack modular synthesizer systems. Where the original CS-80 consisted of a high-pass filter fed into a low-pass, the SE88 offers two modes: Mode 1 consists of high-pass or band-pass that feed Mode 2’s low-pass and band-pass. This can also be done in reverse for even more sonic variety.
Every aspect of the filter’s audio signal is controllable via input and output level knobs, which can be positioned in different ways to achieve an array of tones. Each of the module’s filters utilizes attenuverters for both frequency and resonance experimentation and degradation. While it doesn’t self-oscillate, it is capable of characteristically squelchy sounds. There’s also a master FM attenuator-controlled level routed to both filters at the same time, and tracking switches that enable individual keyboard response for each filter mode.