Pedal Mod for Bass?

Chuck D. Bones

Circuit Wizard
I've been asked to write an article on a pedal mod that is focused on bass. Any ideas? Has to be targeted at a commercial pedal.
 
The input caps are usually what I do, which is almost never. It’s really only necessary in some, but not all dirt pedals. I’ve been playing bass for about 35 years now. I don’t know everything, just some things.😜
 
I keep hearing that bass players like clean blends on their overdrives and fuzzes... what I have tried so far on guitar with clean blend I personally didn't like a lot, but then I ain't playing bass. I will refrain from making inappropriate bass player jokes at this stage.
 
Input caps are a good place to start, but you usually need more than that for a really good response. In my experience clean blend is usually favored because so few dirt pedals can handle the low frequencies well, so they make up for the sub-par response by adding clean blend. I prefer to tweak the response of the circuit itself. I'm not a bassist (I'm actually primarily a drummer, don't tell anyone), but I build primarily for bassists because somebody has to, they've been largely neglected in the boutique pedal world.

To the original question, the commercial pedal that I've been most pleased with modding for bass is the Rat. It's meh for bass stock, but with the right changes it really kills as a bass drive.

I also tried some bass mods for Klon I read somewhere that I really liked the results of. Trying to remember where I read those.
 
If you change the input caps, wouldn’t you also need to increase all caps in the audio path I.e. coupling/output? Just letting bass in the front door may cause the circuit to overdrive more, but you will still remove the bass frequencies with every cap the signal encounters.
 
If you change the input caps, wouldn’t you also need to increase all caps in the audio path I.e. coupling/output? Just letting bass in the front door may cause the circuit to overdrive more, but you will still remove the bass frequencies with every cap the signal encounters.
Input cap, coupling caps, and tonestack caps is what I consider "bare minimum" for an op-amp based circuit.
 
Retuning a Klon Klone for bass sounds like an interesting opportunity. Can anyone point me to some mods? I can make some up, but I'd rather see what others have tried first.
I found the one I used, it was Coda, though he says the mods actually came from Madbean. There's a section near the bottom "Using the Klon Centaur with a Bass".

 
Retuning a Klon Klone for bass sounds like an interesting opportunity. Can anyone point me to some mods? I can make some up, but I'd rather see what others have tried first.
Aion has some bass modes for a Klon in his Refractor build docs.

I'd like to see a clean blend circuit that had a boost stage for the clean signal. Basically a parallel split with a volume control on the clean for blending. The circuit I use currently is Barry's Buff-N-Blend. It works well most of the time but if the drive is much hotter than the clean, it loses it's usefulness. It be cool to know what blend circuit Aguilar uses on their bass offerings.
 
Aion has some bass modes for a Klon in his Refractor build docs.

I'd like to see a clean blend circuit that had a boost stage for the clean signal. Basically a parallel split with a volume control on the clean for blending. The circuit I use currently is Barry's Buff-N-Blend. It works well most of the time but if the drive is much hotter than the clean, it loses it's usefulness. It be cool to know what blend circuit Aguilar uses on their bass offerings.
Another good lead, thanks. Since the Klon's GAIN control doubles as a clean / dirty blend, it should be possible to rebalance the relative gains of the clean & dirty paths so that the clean channel is dominant over a larger range of the GAIN knob.
 
Another good lead, thanks. Since the Klon's GAIN control doubles as a clean / dirty blend, it should be possible to rebalance the relative gains of the clean & dirty paths so that the clean channel is dominant over a larger range of the GAIN knob.
Now that you mention it, splitting the Gain pot would give the control I mentioned before. Too bad the Klon is such a boring drive, lol.
 
Grind Customs created a bass klon with a boost, it never left my pedal board. I really like it.
Not much change from a stock Klon. A boost was added, +18V rail deleted in favor of +9V, R11 increased to 1M and R3 added. No changes to the freq response, which is surprising.
 
Now that you mention it, splitting the Gain pot would give the control I mentioned before. Too bad the Klon is such a boring drive, lol.
I built the VFE Merman (PedalPCB Sea Monk]. The split GAIN control is ok, but doesn't do all that much more that a ganged GAIN control. Because of the complicated network feeding the 3rd stage, there is a fair amount of interaction between the two halves of the GAIN control. Specifically, turning the CLEAN GAIN pot affects the DIRTY channel's equalization. There are some simple changes that strengthen the Clean channel and the Bass bleed. I definitely recommend building the Merman or Sea Monk if you want to experiment with Klon mods.

As for being a "boring drive," the irony is not lost on me. It's supposed to be a boring drive. The only thing exciting about it is the hype.
 
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Re Centaur: As already mentioned, make the dual-gang gain pot two separate pots. GPCB has a fat mod. I’ve cobbled together a few bass mods for the Klon, but don’t have access to my notes, currently.

I thought your request in the OP was more for a specific circuit, and all I wanted to suggest was choose something other than what’s already done (ie Muffs, TS-808, Rat etc).

The Way Huge Fat Sandwich, I’m told, is inherently difficult to mod for bass. Katzenkönig was another.


Or bassify some modulation, or a compressor…


Aion has a few projects listed as being specifically unfriendly to low end. Meteor, maybe? Cuts bass around 1.5kHz before clipping…

Wish I had my computer back, the doctor said it was terminal and had to be put down — though he will be able to save the HD. If I get it back in time I’ll be able to be more specific on the Aion stuff and maybe some other ideas.

Very much looking forward to your article be it on the Klon or any other circuit.


Meanwhile…
All your bass are belong to us.
 
The EHX Bass Soul Food is a Bass version of the Klon Centaur as far as I know. I have it and it has not the Low End needed for serious bass use, although it has a Blend knob for the clean signal.
JHS came up with some mods for the Bass Soul Food in the past to fix that, but it is not easy to find what they did there.

There is a complex DIY Pedal called Omnilooper, where you can insert any guitar effect to make it suitable for bass.
 
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