Deadringer 2 Boost Bias issues?

[playpunk]

Hello all:

I just finished my deadringer 2 and threw it on my test rig for a minute. The OD side is lovely, the clipping options are both fantastic, and I like it a bunch.

I am having some problems with the boost side, and am getting a bunch of distortion no matter where the bias is set. It also seems very very dark, and the "cut" knob doesn't seem to have much effect.

Are there any voltages I should try to bias my JFET's to? Are these bad JFET symptoms?

I will try to get some pictures up tonight, but those were my lunctime impressions.

[brejna]

I think boost is meant to be used with drive side only. Mine too is bit dark when used alone, but it works great with drive side. I can get unbelievable differnt tones with it. Also I did set mine trim to 4.5v

[playpunk]

I think boost is meant to be used with drive side only. Mine too is bit dark when used alone, but it works great with drive side. I can get unbelievable differnt tones with it. Also I did set mine trim to 4.5v

Huh - The build doc says that the boost is independent. I don't really want to be reading RG Keen's articles about boosters, but I am now trying to figure this stuff out.

This is how I started building pedals - looking at "gateway" websites like the Madbean projects page. I really don't need to be designing or analyzing circuits too.

[madbean]

The boost is independent, for sure. Based on some user feedback it looks like it does tend to be dark in some setups. What I suggest is reducing C18 from 47uF to 10uF or 4u7. You could go as low as 1uF, but you may lose some overdrive with that.

Q5 should be biased to about 4.5v as the build doc states. There's no other bias to set as the JFET is a buffer.

I'm curious about the cut control not working. You should have a very noticeable brightening of the signal when it is fully up. Are you sure you have used 1k5 for R26 and 6n8 for C20? Maybe double check those.

Lastly, how about your J201s? Where did you get them from?

[playpunk]

The boost is independent, for sure. Based on some user feedback it looks like it does tend to be dark in some setups. What I suggest is reducing C18 from 47uF to 10uF or 4u7. You could go as low as 1uF, but you may lose some overdrive with that.

Q5 should be biased to about 4.5v as the build doc states. There's no other bias to set as the JFET is a buffer.

I'm curious about the cut control not working. You should have a very noticeable brightening of the signal when it is fully up. Are you sure you have used 1k5 for R26 and 6n8 for C20? Maybe double check those.

Lastly, how about your J201s? Where did you get them from?

Well I feel like a dork - I thought that the cut control cut more treble the more it was up. I will check my values and joints on those components.

My j201s are from DIY stompboxes, so i assume they're good, and I didn't socket them as I've not had problems biasing others from that batch before. I might have to put my new solder sucker to use...

And sorry about the bias issue I was probably just blowing through the build doc too fast.

I will check back in with the results.

Thanks!

[playpunk]

Biased the jfets at 4.45 v and dropped the 47u cap to a 4.7 u and things are much cleaner.


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[playpunk]

I had to put the new electro on top as I had an issue with the old one. It is flat of course


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[playpunk]

I had some time at lunch today to play with this a bit. Here are my thoughts:

1. The boost is not a very useful effect on its own. It is (even with the 4.7 uf ) quite dark, even with the "cut" knob rolled all the way back. I tested it using a CV Strat into a Vox ac4c1 and it was not very usable, in my opinion.

2. The boost is really excellent when stacked with the OD. The treble cut inherent to the design doesn't make as much a difference, and the effect works like another channel, with different OD characteristics.

3. The OD side of the pedal is excellent, although if I build another one i think I will go with the timmy style bass control instead of the rotary switch.  I find the effect subtle, but I guess that could be the result of subbing a 220n instead of 270n for the biggest cap.

Maybe I'll get this boxed this weekend. I have a green bean, 8 ball, slo loris, lowrider, deadringer, behemoth and "the beast" populated and tested..... I need a full time graphic designer on staff, but seeing as Playpunk pedals, LLC is way in the red, I think that would be a foolish decision.