MichaelW
Well-known member
- Build Rating
Here's another build that was totally not on my radar until I heard @szukalski talk about how much he likes his.
I have the updated version of this board that has the onboard trimpots. I can't imagine trying to dial in the bias without the trimmers and probably would have installed some if I were using the old board.
Even with the trimmers the biasing is tricky and this circuit seems to be pretty sensitive to the spec's of the J201's.
I found this thread of course AFTER I had already built it. I usually do a bit of research and look for troubleshooting threads before building a pedal but skipped that this time to my own detriment. I found out that this pedal seems pretty finicky with the JFET's and some sorting is in order.
I actually have a second Chop Shop board (because @PedalPCB seems to have problems counting, hahaha, he sent me an extra board) that I may build out using that thread as a guide.
I decided to use the SMD J201's and this is the first attempt at soldering an SMD besides an FV-1. It was an......interesting experience.
Not sure I would want to do a whole board this way, but I think I managed ok with only a couple of components.
I initially biased it by voltage on my bench. I got Q1 to about 5 volts but could not get a consistent reading on Q2. So I said screw it, fired it up and biased it by ear.
I'm still messing with it but I "think" I have it where it sounds like its supposed to. I haven't gone back to check where I landed.
With the bias settings where I have them on Q1 I don't have a lot of output. Unity is around 1 o'clock. If I dial it where there it more output, it's very clean output only and I seem to lose the clipping. So I'm not entirely sure if this is expected behavior, or spec's of my J201's or what.
Tonally, this has some of the same transistor clipping vibe of the Benson Preamp, although a bit more angular and less smooth.
At higher gain settings it can sound fuzzy and gated. So far, I've had it with the gain knob set fairly low, and the SAG set pretty low, then boosting it with the Clandestine Preamp, great low gain sounds. Sounds pretty good with my Tele and sounds REALLY good with the P90 Tele.
But definitely still needs some dialing in.
I decided to go for the same vibe that Fairfield does with their unpainted enclosures. I used a genuine Hammond 1590B and genuine Davies knobs.
Holy crap those things are small!!!!
I have the updated version of this board that has the onboard trimpots. I can't imagine trying to dial in the bias without the trimmers and probably would have installed some if I were using the old board.
Even with the trimmers the biasing is tricky and this circuit seems to be pretty sensitive to the spec's of the J201's.
I found this thread of course AFTER I had already built it. I usually do a bit of research and look for troubleshooting threads before building a pedal but skipped that this time to my own detriment. I found out that this pedal seems pretty finicky with the JFET's and some sorting is in order.
I actually have a second Chop Shop board (because @PedalPCB seems to have problems counting, hahaha, he sent me an extra board) that I may build out using that thread as a guide.
I decided to use the SMD J201's and this is the first attempt at soldering an SMD besides an FV-1. It was an......interesting experience.
Not sure I would want to do a whole board this way, but I think I managed ok with only a couple of components.
I initially biased it by voltage on my bench. I got Q1 to about 5 volts but could not get a consistent reading on Q2. So I said screw it, fired it up and biased it by ear.
I'm still messing with it but I "think" I have it where it sounds like its supposed to. I haven't gone back to check where I landed.
With the bias settings where I have them on Q1 I don't have a lot of output. Unity is around 1 o'clock. If I dial it where there it more output, it's very clean output only and I seem to lose the clipping. So I'm not entirely sure if this is expected behavior, or spec's of my J201's or what.
Tonally, this has some of the same transistor clipping vibe of the Benson Preamp, although a bit more angular and less smooth.
At higher gain settings it can sound fuzzy and gated. So far, I've had it with the gain knob set fairly low, and the SAG set pretty low, then boosting it with the Clandestine Preamp, great low gain sounds. Sounds pretty good with my Tele and sounds REALLY good with the P90 Tele.
But definitely still needs some dialing in.
I decided to go for the same vibe that Fairfield does with their unpainted enclosures. I used a genuine Hammond 1590B and genuine Davies knobs.
Holy crap those things are small!!!!
