GuitarPCB's Bass Overdriver : Blend control and bass boost toggle mods.

eh là bas ma

Well-known member
I built the GuitarPCB Bass Overdrive a couple of years ago, never really could enjoy it because of some kind of bass cut. Compared to other Bass dirt circuits, it felt like it was missing some depth or something.

I always liked something about it though, it sounds quite convincing as a Bass tube amp emulation.

Two days ago, I thought about adding a clean blend control, in order to restaure a bit of bass frequencies in the distorted signal. I wasn't sure how to do this, so I posted about it on diystompboxes.

The final result is far beyond my original expectations.

Thanks to the amazing help of dear forumites, I ended up building an extra buffer on perfboard to fix a "quick hack" for the blend control, and using a 3PDT toggleswitch to change caps values at three locations on the circuit : an effective bass boost and an extra blend control !

IMG_20230314_063930.jpg IMG_20230314_083653.jpg IMG_20230314_083802.jpg

This was built without mods in 2020 (you can guess from the abundant wiring that it was among my first builds), it's the v.1 :

I am sure these mods can be done on the v.2 currently sold at GuitarPCB's.

All the details about how to build the mods are in this thread :

If you built one of these Bass OD boards, I strongly suggest to consider these mods, I couldn't be happier with how it turned out.
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eh là bas ma

Well-known member
Here is a demo :

Warning : Due to the nature of the test, there can be some volume increases and decreases.

This a loop station sending a bass recording to the Bass OD, the OD is sending the signal directly in an other loop station, recording this demo. No other effects are involved.

1/ from 0:00 to 1:39'

Drive at 12'

2/ from 1:40 to 3:04

Drive set at max gain

3/from 3:05 to 4:18

Drive set at 3/4 of rotation

During these intervals, I only modify the Blend setting, and play a bit with the bass boost toggleswitch (you can hear the click).
I use the Volume knob to lower the level when I turn the blend CW, toward wet signal.