Inspired by the classic Telefunken/AEG U73 - the fastest tube compressor of its time - the Siemens U273 was the world's first solid state compressor, introduced in the 1960s.
The limiter itself is absolutely superb - it features transformer balanced/floating inputs and outputs with lovely big Haufe transformers. The unit is an all-discrete compressor with only one control for release - otherwise it is fully automatic. In use, the Siemens U273 compressor has a fat tone, with a slightly rolled of top end. It sounds creamy and dark.
The Gear Rack