Projects > Gyraf GSSL Buss Compressor
The GSSL is a clone of the stereo buss compressor found in SSL4000-series desks. Because of it’s affordability and relatively low difficulty, the GSSL has become a very popular project with many PCBs and mods available.
Images courtesy of Gyraf Audio and FiveFish Studios
Notable Features:
- Designed for DBX202x or THAT2180/2181 VCAs
- Uses all modern easily sourceable components
- Ratio, attack, and release pots
Possible Modifications:
- Turbo Mod
- Changes the sidechain from summed (mono) to stereo. This makes the GSSL behave more like the original SSL.
- CRC Filter Mod
- Fixes power hum problems inherent in the original GSSL design.
- VU Meter Mod
- Usually GSSL builders use a peak meter. The VU meter makes the “feel” of the compressor closer to, say, the 1176.
- Super Sidechain
- Adds adjustable 60, 90, 130 & 200hz high-pass filters, Tilt-Medium and Tilt-Loud sidechain eq curves, and the option for an external sidechain input.
- Crush’n’Blend
- Adds wet/dry mix control
Price:
- 25€ for PCB from PCB Grinder
- 25€ for GSSL + super sidechain PCBs from PCB Grinder
Modifications:
- $9.95 for Turbo PCB from Expat Audio
- $30 for Turbo kit from DIY Parts Supply
- 12€ for Super Sidechain PCB from Gustav
- $9.95 for VU Meter PCB from Expat Audio
- $6.95 for CRC PCB from Expat Audio
- $16 for CRC kit from DIY Parts Supply
More information:
- www.gyraf.dk.
- A blog about building a GSSL.
- Five Fish’s GSSL build blog with sound clips.
Category: VCA Compressor