The m502 is a stellar optical compressor that is super-clean, letting you dial in light to heavy crush via the intuitive control set.
- Kevin Becca, Mix Magazine



optical compressors

High fidelity optical compressors

As of spring 2017, the m502 500 series module is no longer in production. We will continue to support these products for as long as they are in use. We will coninue building the m102 module.

Introducing the m102 and m502 optical compressors. While both share identical audio circuitry, the m102 is built in a half-rack 1U module, and the m502 in a 500 series rack module.

From gentle dynamic smoothing to full tilt squash, these units deliver open, musical dynamic control that is the perfect companion to our high fidelity mic preamplifiers or any recording chain. All your tracks can now have glorious, easy to use compression which regardless of how much you squeeze, will always end up with their sonic essence perfectly intact.

The heart of the compressor circuit is an optical attenuator - the purest, high fidelity gain control mechanism available. With careful attention to control circuit design, we are able to implement a feedback opto compressor that not only provides a wide range of dynamic control, but remains inherently neutral, open and musical.

Both are full featured units, including input and output level, threshold, attack, release and ratio controls. The m102 includes balanced inputs and outputs, both with parallel XLR and ¼" TRS connectors, along with a 1/4" TRS jack for stereo link or sidechain signal input. The m502 includes connectivity for sidechain input, stereo linking and even the Radial® Workhorse Bussfeed.

While lots of our gear adorns the most expensive recording and audio production facilities in the world, all of it sounds that way, and the m102 & m502 are no exception. We eagerly invite you to hear what truly transparent, musical dynamic control can do for your audio production. The perfect way to zip it all up and send it all downstream: clean, intact and alive.


  • features
  • specifications
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  • artists
  • videos
  • Elegantly simple, purist feedback design optical compressor, optimized for signal leveling with a minimum of sonic artifacts
  • From subtle dynamic control to heavy compression, the sonic character of the source remains intact
  • Comprehensive control set includes input level, threshhold, attack, release, ratio and makeup gain
  • Bright, easy to read 10 segment LED gain reduction meters
  • Bi-color output peak LED lights green with signal present and red 8dB before clipping
  • (m102) dual balanced inputs and outputs on XLR and 1/4" TRS
  • (m502) circuit board header / connector for stereo linking
  • (m502) connections for sidechain, stereo linking, and Radial® Workhorse Bussfeed
  • Precision audio path with 0.5% precision metal film resistors
  • Bombproof laser-etched black anodized frontpanel
  • (m102) Built in universal power supply
  • Five year transferable warranty on parts and labor
  • Built by us in the USA