The Soma Vintage Overdrive is adapted from the Pete Cornish SS-3, traced by Aion FX in 2019.
Cornish pedals are best known for being extremely expensive. There are two reasons for this. First, the build quality and reliability is unmatched. Second, the mysterious nature of them, partially due to the fact that the circuit is obscured and partially because of the A-list of clients such as Brian May and Pete Townshend.
The SS-3 in particular is owned by Jeff Beck, David Gilmour, Keith Urban and Carlos Santana among many others. It’s an update to the earlier SS-2 that adds a low-cut control, since the original was fairly bass-heavy. With the low cut control set fully clockwise, the circuit is identical to the SS-2.
Under the hood, the SS-3 appears to have originated from the MXR Distortion+ circuit and then had passive low & hi-cut tone controls added, along with the classic Cornish buffer at the input.
The Soma is a faithful reproduction of the SS-3 circuit, but with one major addition: an internal slide switch allowing the pedal to be used in true-bypass mode instead of buffered bypass. As with the Klon KTR, the buffered mode is “almost always better”, but with this feature, you can determine for yourself.