Sonic Churn

The result of long collaboration with Michael Landau, this lovely box of tone started life as an SD-9 and grew. And grew.

There's a lot of hyperbole about this being a whole new type of distortion, which is simply isn't. What it is, is a nicely refined development of that original tone. This one is a lot more open and amp-like, rather than the often over-compressed sound of the SD.

The original has two trimmers to adjust the low-mids, essentially adding bottom end beef, and 'sparkle' which adjusts the peak at the 6K mark, adding top end sheen and bite. We've added spots so you can use pots for these, but in tests we found they're really both set-and-forget, so we'd advise keeping your enclosure uncluttered unless you're really into tweaking on the fly.

No-one has been able to determine exactly which op-amps are used in the original, as the part numbers have been sanded off. We've trialled a bunch and decided on OPA2134 and 4558. Sounds good to us, and the OPA really is worth the few extra £££.

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 can take a battery if desired with footswitch positioned 22mm higher, closer to the controls. Knobs are not included.

Inspired by: Butter Machine

Difficulty: Medium

PCB size: 50 x 50mm

Knobs required: 5

Enclosure: 1590B

Direct Connect compatible (4-way)

Download the INSTRUCTION PDF