Variable Gm

Stereo tube compressor

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The Variable Gm compressor limiter is modeled after a design which has made the history in the audio compression world, with a sound limpid, crystalline, and crisp at the same time, where compression starts low and increases gradually, so subtle and natural, but punchy when driven hard. The unit is quieter than any other tube compressor and it manages to provide the vacuum tube warmth that tube circuits are renowned for without adding any negative artifacts or noise.

The Variable Mu technique enhances the vocals and individual instruments by being unobtrusive, gently warming sounds, impressive on overall mixes. The 'Stereo - Dual Mono' working mode ensures the widest freedom of use for the most demanding studio applications, as a tracking or mastering compressor. The external special custom order 'Surround Link' allows several units to be linked for Surround 5.1 or 7.1 operation, making this compressor the ideal choice for this application ranges to set a quality standard.

The components used are all selected with the strictest tolerance, and tested by ear. It broadens the base of your mixes.


  • Twin channel Variable-µ compressor limiter
  • Stereo or Dual Mono operation
  • Ideal for Stereo bus, Mastering and Mixing applications
  • Meter switch for input, gain reduction and output monitoring
  • All valve-based circuitry, totally analog processing
  • Inductively filtered plates supply, fully filtered and regulated heaters supply for lowest noise
  • Entirely balanced signal route for improved noise rejection
  • Automatic compression ratio
  • HPF on side chain for superior versatility
  • Continuous rotary controls, step controlled release
  • True hard-wired bypass
  • Linear frequency response over the entire audio range and beyond

Technical specifications

  • Frequency response (+0/-0.5dB): 15Hz—20kHz, (-3dB): 5Hz—44.1kHz
  • C.M.R.R., 1kHz: ≥60dB
  • THD+N, -3dBFS, 1kHz: -102dB
  • Signal/noise ratio, ref. 22 dBu, A-weighted:  ≥90dB
  • Maximum output level for 1% THD+Noise, load: 10kΩ: 26 dBu
  • Maximum gain: 26dB (standard vers.), 23dB (mastering)
  • Input impedance: 20kΩ
  • Output impedance: 250Ω
  • Dimensions (W x H x D) inches : 19 x 5.24 x 20.87
  • Net weight: 20.6kg (45.42lbs)


Product inquiry

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