Traynor TS-50B Preamp

Pre-amp of the highly sought-after Traynor TS-50B bass amp. The unmistakeable tone of Shellac-era Steve Albini, Bob Weston and David Wm. Sims.

The circuit is almost identical to the guitar model other than the tone section, the bass model having entirely passive BMT controls rather than the active Mids gyrator circuit on the guitar version.

The circuit has some unique elements. The op-amp and Fender style tone stage are fairly standard, but after the tone the signal is split into 3 bands, each of which is distorted separately. Why? Ask Traynor's engineer for the technicals, but tailoring the compression to the individual bands makes for some really sweet clipping.

Lots of headroom thanks to the very expensive +/-15V DC converter supplying the juice.

Note: With gain and EQ cranked you may get high-frequency oscillation depending on your setup. This can be mitigated by having this circuit in a buffered chain, or simply winding things back a bit. You hve been warned. If you aren't happy with that, don't order.

If you go for top jacks we'll supply Lumberg jacks so they'll fit nicely above the pots.

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

Partial kit: PCBs, all board-mounted components (not footswitches), 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. Please choose appropriate knobs.

Inspired by: Traynor TS-50B Preamp

Difficulty: Medium

PCB size: 80 x 50mm

Knobs required: 5

Enclosure: 1590BB

Download the INSTRUCTION PDF

Product Code: ts50B

Brand: Pedal Parts

Product Condition: New

Kit type Jack position* Ribbon cable*

£60.00 inc. tax

£50.00 ex. tax

? Tax based on United Kingdom.

Customer Reviews

1 review(s) posted (write review)

Headroom and Great Tone Controls
"As with every Fuzzdog kit, this goes together like a dream and mounts into the enclosure to make a reassuringly solid gig-worthy pedal. Speaking of gigs, this circuit really shines in its tonal flexibility, the bass, mids and treble all sound great at 12 o clock so you have lots of room to roll back muddy, nasal or harsh tones, or boost whatevers lacking. Nice grit from the gain control, don't expect anything crazy or fuzzy though! Also useful if you need a bit of extra headroom in situations where the venue amp or PA is a little underpowered, although in the spirit of preserving musician-soundtech relations I should caveat that this is a last resort and should be clearly communicated at sound check... Don't flick that boost switch recklessly!" Aleks - 03 November 2026