The Mastercom is the small sibling of the Behringer Combinator. It's a two-band stereo compressor/leveler + limiter/clipper in 19" 1U format with the choice of two crossover frequencies.
It features jack and XLR connectors working at professional +4dB nominal level. That means that when it indicates 0dB the output level is + 4dB.
Very easy to use. You only need to activate it, set the compressor's threshold, ratio, the relation between compressor and leveler or simply compressor or leveler, and, finally, the threshold of the limiter/clipper and the output level.
It shouldn't take you more than five minutes to get a decent sound.
It's a pity that it doesn't have attack and release controls to amuse yourself. But, on the bright side, you don't need to rack your brains fiddling with them. It can also put up with high levels.
The compression is obvious with this unit! The sound has a particular color. Low level signals are nicely boosted. The loudness improves substantially. The limiter/clipper is incredibly effective, even when pushed to the limits, but it sounds somewhat metallic.
Yet another weird unit on the secondhand market. It's robust, easy-to-use and effective (but be careful, it's not an orban optimod 8100a either, but anyway.
It's not bad at all to get a good compression with personality.
All things considered, this Behringer product is quite all right without being a legendary unit, obviously (it's not a BSS DPR402!)