JC Emerald

The JC Emerald is based on the preamp of one of the best known British tube amps of the 1980s. It has been modified to make it more suitable for pedal/preamp use while staying true to the original tone. This latest version includes some additional toggle switches to make the preamp design more flexible.

Brite switch on – stock preamp

Both switches off – treble rolled-off

Deep switch on – low-end boost

The intention was to make the preamp more useful for bass, but it also makes it more flexible for guitarists that want the classic British gain structure but without the aggressive treble of the original circuit or that want more heft behind their tone. My preferred guitar tone (since I find the original a tad bright) is to leave both switches off, and my preferred bass tone is to leave brite off and turn on the deep. If you’re looking for that Lemmy-esque bass tone, try turning both switches on for some extra low end but some nice sparkly grind up top.

The Summer 2024 revised edition of JC Emerald has the same great circuit as before, but now with upgrades like film capacitors in the audio path and soft-touch relay bypass switching.

As a tube pedal, JC Emerald requires a high amount of current to operate correctly. I recommend a 9-12VDC power supply capable of delivering at least 600mA. Using less than this can damage the power supply and/or the pedal.

Enclosure size: 4.7 in x 3.7 in x 1.34 in (119 mm x 94 mm x 34 mm)

Check out this review/demo from the guys at BASSED.