Got this from an estate auction. Powers on. From what I can make out it seems to be in working order. I was able to test input 1,2, & 3, and the main output and they all work (tested With vocals and snare). Battery compartment is empty but seems jammed. Didn’t want to force it open and potentially damage it. Seems like previous owner tried which added the scratches to the cover that is pictured. That’s about the extent of my abilities to be able to test. That’s why it’s listed as fair even though seems to be in working order.

I have quick videos of me testing the inputs and output. I can send a dropbox link if interested.

**from online forums**

The Shure Model SE30 Gated Compressor/Mixer is a high-quality device designed for professional applications in AM, FM, and TV broadcasting, film, tape, and disc recording, CATV, and sound reinforcement. It combines a gated memory compressor with a self-contained, portable, three-input mixer and remote amplifier.

Here are some key features of the Shure SE30 Gated Compressor/Mixer:

Three Transformer-Coupled Inputs: These inputs are switchable between low impedance microphone or line level.

Individual Feedback-Type Level Controls: Each input has its own feedback-type level control to provide maximum clipping and minimum noise levels over a wide dynamic range.

Stereo Parallel Jack: This feature allows for synchronizing the compression circuits of two units.

Frequency Response: The device has a flat frequency response of ±2 dB from 30 to 20,000 Hz.

Noise Levels: The equivalent input noise is -129.5 dBV maximum (Microphone input, 150 ohms, 20 kHz equivalent noise bandwidth with a lower cutoff frequency of 300 Hz, at full gain).

Output: The output is specified when the input controls are set to minimum.