Ballou (GCI Gradient Boost) Volume Issue

[sam2020howard]

I have had this GCI boost for quite a while, and while I love what it does it is way, way, too loud. I’d like to get maybe like 60% of the volume but keep the distortion and eq sweep that come out of it, but I am wondering if you guys could advise on my options.

1) I’m aware I could probably get a volume pot in there, and that that would provide the most control, but it’s a brutal (in a cool way) looking pedal right now and I’d just as soon not add a knob. I thought about doing a trim switch on the side, but that may be too complicated for me to wire (I do have an on/on/on dpdt and lot of resistors though, if this is not as dumb in practice as it seems in my head)

2) My current solution is just to run it into a Keeley comp as limited. I don’t love this, as I still want it to push the pedal after it (Shallow Water), but with the compressor (or I guess limiter the way I’m using it) off the SW has so much headroom the output signal clips the next pedal

3) probably the easiest solution to my mind would be to hardwire a resistor somewhere in this circuit that doesn’t effect bypass, but limits the output. I just don’t know where to add that. My guess would be on the pcb side output cable?

4) lastly, I could pull or add components to the board, but I’m having trouble finding any material on this circuit (correction: https://kurtballou.com/docs/GOD CITY INSTRUMENTS - Gradient boost V1.1 Build guide.pdf is a guide, I mean useful pertaining to making it less loud), and while it’s not functional to me at the moment, that doesn’t mean it won’t ever be, so I’d like to avoid destroying it in a way that I can’t troubleshoot (pulling components with unknown values and replacing them is a bit scary)


Any advice is appreciated. Thanks!

Photos attached

 

[SpringReverbFan1234]

3) probably the easiest solution to my mind would be to hardwire a resistor somewhere in this circuit that doesn’t effect bypass, but limits the output. I just don’t know where to add that. My guess would be on the pcb side output cable?

Yeah, you could cut the output wire at the jack. Then add a trimpot as a volume. Or two resistors as a voltage divider; run a cable to a breadboard to play around with the values first. Or keep it stock and build a little separate volume knob pedal.
edit: I realized you said not affecting bypass. You'd have to cut/desolder the effect output wire and add stuff before the 3pdt board.

 

[lowpitch]

Adjust the voltage divider formed by R7 and R6. I'd start with R6 = 10K and adjust up or down for less or more volume cut. R7 can stay. If you don't want to desolder R6 you can put a resistor across board output and ground. R6 will then be in parallel with this new resistor. Keep in mind the parallel resistance will be less than either resistor value.
Don't put a resistor across the output jack as this will also affect the bypass signal.

 

[sam2020howard]

Thanks guys.

I appreciate the input on the resistors, but I don’t have a breakout to test different values, so just wanted to ask what started off as one question and turned into three:

If I like the idea of throwing a trimpot on the “effect out” which in the photos (backside of pedal) I am assuming is the far right wire, that one would run from effect out to the “trimpot in” and then another trimpot leg would run to “3dpdt in” is that right?

And would ground form the trimpot need to run to ground separately, or would the ground leg serve as a bridge with the pcb ground running to the trimpot leg and then running from the same leg to the “3dpdt ground”

And is 20k going to work as far as trimpot value? I’ve used all my 50k elsewhere.