Germanium Tart

All-germanium overdrive supposedly used by some pretty big hitters (maybe Ryan Adams, Radiohead, Eagles of Death Metal... there's a long list).

Is it worth the hype? Yeah, well. It is pretty good. It has a fairly unique set-up as far as we're aware, using three PNP cans in a negative-ground circuit. The results are rich and warm break-up that's quite convincingly tube-amp like.

We've added trimmers for you to bias the transistors to perfection, or your own taste anyway. We've also tweaked the values of two of the pots as the response with the original values is awful. Linear pots for Gain and Tone have all the adjustment bunched at an exreme end of the turn. We've subbed a reverse log for Gain and a log for Tone which are much better. The gain is still a bit bunched, but more useable.

Kit comes with a set of germanium transistors of various types (usually Russian) of the correct hFE for the circuit. You can opt to have it without transistors if you have your own.

The kit is supplied with vertical-mount pots which have round shafts, so you'll need set-screw fitting knobs.

If you want the PCB without parts there's a link for that at the bottom of the page.

Partial kit: PCB, all board-mounted components, pots.

Full kit: As above, plus footswitch and appropriate daughterboard/components for your selected bypass type (see Downloads section for details of those), jack sockets, DC socket, battery snap, hook-up wire, LED.

Enclosure (pre-drilled) is available as an option with full kits, and will not take a battery. Knobs are not included.

Builds are only available with full kits including enclosures and vertical-mount pots. Please choose appropriate knobs.

Inspired by: TA-100

Difficulty: Medium

PCB size: 50 x 43mm

Knobs required: 3

Enclosure: 1590B

Direct-Connect compatible (4-way)

Download the INSTRUCTION PDF