Sigma 500™ Specifications

  1. *Input: 32 channels via Dsub, 2 channels via XLR

  2. *Output: 2 channels via XLR

  3. *Odd channels wired to channel 1, Even channels wired to channel 2.

  4. *Power: Switchable for 110/220v on IEC inlet

  5. *DC Power Output: +16v/417ma

  6. *Chassis: 2u Durable Steel


The Sigma 500® is a 32 channel passive summing box that uses your 500 series compatible preamps in either single or dual sizes, and it also pulls double duty as a 2 in x 2 out powered rack.  There are 3 separate modes. 

  1. -In SUM mode, your two preamps act as summing amps for the left and right channels.  The odd numbered input channels are wired to the left preamp and the even numbered input channels are wired to the right preamp.  Sending stereo panned tracks from your DAW will allow more intricate panning. 

  2. -In ALT mode, the alt XLR inputs are sent directly to the modules, bypassing the summing portion. This mode is most often used with your mic preamps in a recording situation.  However,  it can also be used for powering other 500 series compatible products like EQs and compressors.. 

  3. -In PASSIVE mode, the passive summing circuitry is isolated so you can use it with preamps other than the 500 series type, such as rack mount or table top preamps.

There are no hardware faders or pans to worry about recalling correctly. This means you can go from mix session to mix session and not have to worry about recall …one less thing you have to think about when mixing. 

The Sigma 500’s support of 500 series preamps allows for quick tonal color changes.  Say you are looking for a different color for a particular mix, well it’s as easy as taking preamp set A out and popping preamp set B in.  You can make the preamps you already own pull double duty for tracking, and now, mixing.  Also, pairs very well with the A-10 to allow you to saturate your mixes even further. 

Documentation Download:

Sigma 500 manual.pdf

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Sigma 500®

32 Channel Summing/Powered rack

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Sigma 500

Sigma 500 Reviewed in Tape Op Magazine!   

Check out what Garrett Haines of Tape Op has to say about the Sigma 500 here: