Inspired by the performance of a classic FET leveling amplifier and the simplicity of much-loved vintage compression stomp boxes, Walrus Audio has packed a studio-grade compressor into a guitar pedal.

Fitted with Level, Sustain, Attack, and Blend knobs, the Sealion delivers tremendous versatility. Active, passive, humbucking, or single-coil; the Sea Lion is ready for all your electric guitars.

The original design by Walrus includes an internal charge pump to make this pedal operates at 18v from a 9v power supply. On this design, we choose not to include a charge pump on board in order to keep the layout tidy and tight to fit on a 125B and to give you the option to choose between plugging it into 9v or 18v from your power supply. Higher voltage will result in more headroom and crystal clear tones.

This design has been optimized for the proper performance with the IC LM13700 instead of the discontinued CA3080 normally associated with compressors from the DynaComp/Ross family.

It’s recommended to operate this circuit at 18v, but remember that all the capacitors should be rated for more than 25V.

Sea Lion Compressor Building Docs

Sea lion compressor – Drilling templates

For further analysis on this circuit take a look at this thread on Free Stomp Boxes Forum

For anything technical question regarding this build don’t forget to check out our Facebook Group, and our forum at Free Stomp Boxes