L-1 Microcompressor Stereo


Out of stock



MICROCOMPRESSOR STEREO – compact stereo VC compressor

This is compact but hi-quality compressor, using the THAT4301 dynamics processor.

THAT 4301 Dynamics Processor, dubbed “THAT Analog Engine®”, combines in a single IC all the active circuitry needed to construct a wide range of dynamics processors. The 4301 includes a high-performance, exponentially-controlled Blackmer® VCA, a log-responding RMS-level sensor and three general-purpose opamps.

Design is based on THAT Corp. design notes – Fully Adjustable Compressor / Limiter. This is a feedforward VCA compressor.


  • Adjustable by potentiometers Treshold, Ratio, Attack, Release, Makeup gain.
  • Reduction LED which lights when signal level exceeds treshold.
  • Treshold, Makeup, Attack and Release can be controlled by CV.
  • Hard/soft knee switch.
  • Two timing modes are available — auto and manual. In auto mode attack and release rates are linked, and depend on the non-linear capacitor circuit. In manual mode, variable, independent adjustments of the attack and release dynamics are possible.
  • Peak or Automatic timing detector options.
  • Sidechain in to external sidechain processing.
  • Envelope out allows to patch any VCA as compressor.
  • Full reverse polarity protection.


Power consumption: V+ 43mA, V- 30mA.


Soundsample. Tube VCA works as compressor modulated from envelope out of Microcompressor. Filter – Mutant vactrol VCF. No effects.


Sample made by Jim Sutherland www.jimsutherland.uk.com/ 
Distorted drums in punk style are heavy compressed. Jim modulated Makeup from Envelope Out to have extremally strong compression.