Sea Lion Compressor

Project overview

Based on Walrus Audio Deep Six Compressor with roots on the DynaComp and Ross Compressor. This four knobs beast works great for guitar or bass thanks to the internal trimmer that regulates how much the signal is fed into the IC.

Designed to operate with the IC LM13700 instead of the obsolete CA3080 that most of the compressors use. It’s recommended to operate this circuit at 18v, but remember that all the capacitors should be rated for more than 25V.

Introduction

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

Fitted with Level, Sustain, Attack, and Blend knobs, the Sea lion 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 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.

Controls

• Attack: lets you optimize compression for either low- or high-output instruments.
• Ratio: Acts as a blend knob, perfect for mixing in a portion of the uncompressed signal for a more

  natural sound.

• Sustain: Controls the amount of compression. Turn it up to increases the sustain.
• Volume: Controls output of the pedal
• Trim1: attenuates the signal going into the LM13700, originally in this circuit, to compensate

  production differences of the original CA3080, on this build with the LM13700, this trim pot should

  not have that much importance; just place it in the middle and forget about it.

For further analysis on this circuit take a look at these threads on Free Stomp Boxes Forum: Deep Six Compressor and Deep Six Compressor Schematics.

For any technical questions regarding this build don’t forget to check out our Facebook Group and our forum at Free Stomp Boxes.

Sea Lion Compressor – Building Docs

Sea Lion compressor – Drilling Templates