Bad Mofo Bass Overdrive Preamp

From the vendor

Now available in a 1590B version. If you like a smaller box, go check that out.

All new for 2022, this updated version now has a separate daughterboard for the rotary switch. Why? It makes it much easier to get the switch level with the pots for neat enclosure mounting. You know it makes sense.

Some special lovin' for all you low-end dirt junkies. The Bad Mofo bass overdrive preamp.

DRIVE and LEVEL pots give you control over the amount of dirt and volume. TREBLE is a low pass filter to cut your top end for just the right amount of fizz. Nothing groundbreaking there, but wait....

We have a four-way rotary switch to give you four completely different sounds. Silicon, Germanium and LED clipping are available, as well as clipping bypass for extra crunch and minimal clipping.

Top off those goodies with a very effective buffered BLEND control to dial in as much dry signal as you like.

The only bass dirtbox you need? Maybe. Be sure to take the path of the righteous.

Note: The rotary switch will normally have a long shaft and will need to be cut down to size. No longer supplied with the 4562 op-amp as they're simply not available. 4559 supplied instead.

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.

1590BB 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 only with board-mounted pots. Please choose appropriate knobs.

DC socket can be in one of three positions as shown left

Inspired by: Ezekiel 25-17

Difficulty: Medium

PCB size: 78 x 36mm

Knobs required: 5

Enclosure: 1590BB

Direct-Connect compatible (4-way)

Download the INSTRUCTION PDF