Klon / Sunking v3 has very low buffered output please help

[Hav]

Hey guys

Built the sunking v3, have decent voltages on ICs and Transistors but the buffered bypass is very very low. When the pedal is engaged, even a few mm turn of the volume Pot, the volume is very loud compared to the bypass..

anyone have any ideas on what this could be?

Thanks
H

[midwayfair]

Is your buffered volume similar to your volume going straight to the amp, or is it just too much boost?

[Hav]

further testing shows that:

when the volume is around 1/2 to 3/4 turned, the bypass volume is then the same as the volume as going from guitar direct to amp....

so it seems the pedal is just too loud? what could this be?

[grwadley]

Did you ever solve this issue? I'm currently experiencing the same thing. Sounds great when engaged, and has plenty of volume, but it cuts a lot of my volume when I disengage it.

[midwayfair]

Again, is it quieter when bypassed compared with when the pedal is not in the chain.

Hav, check you didn't use 560K instead of 560R.

[mgwhit]

I would suggest that you both check the value of your R27 resistor.  It should be 560R (i.e. Ohms) not 560K (or any other multiple).  Putting a higher value resistor there will cause a loss in volume on the buffered bypass output.

[grwadley]

Just checked the value of R27 and it seems to be correct. If I chose to switch the wiring to true bypass to solve this issue, would it be necessary for me to removed the unused components? Or do I just need to add in the RPD resistor?

Thanks

[mgwhit]

I can't answer the question about removing components if you're moving from buffered to true bypass.  The doc says to omit R21, R22, C18, R26 and R27 for true bypass, but I don't know if that's because they would interfere or if that's because they're just unnecessary.  Maybe someone else will chime in on that one.  (Just looking at it, though, R21 and R22 look like they should probably come out -- they're the resistors that used to be wired directly to the 3PDT in earlier versions of this and the Kingslayer.)

But let's talk about Jon's question:

Again, is it quieter when bypassed compared with when the pedal is not in the chain.

The standard B10K volume pot in this circuit produces a LOT of volume early in the rotation -- the original designer did it that way so that it could easily be used as a clean boost without any dirt dialed in.  This may be what you're noticing, which is (probably) why Jon asked what he asked.  You need to compare the pedal volume in buffered bypass mode to plugging your guitar straight into the amp.  (A true bypass looper would be really handy here!)

If you still detect a significant volume difference between buffered bypass and straight into the amp, then, yeah, you've got a problem either in your buffer or in your wiring.  I'd love to see decent pics of your board before you modify anything.  I'm always in favor of at least trying to find problems before you start modding around them.

Earlier in the thread, Hav seemed to suggest that his Volume pot affected his buffered bypass volume:

when the volume is around 1/2 to 3/4 turned, the bypass volume is then the same as the volume as going from guitar direct to amp....

If that's the case, something is really wrong.  Please let us know.

[grwadley]

Earlier in the thread, Hav seemed to suggest that his Volume pot affected his buffered bypass volume:

I hadn't seen this post. None of the pots have any effect on my bypassed signal, which I believe is a good sign. I'll get pictures tonight and post them, but I'm leaning towards making it true bypass

[mgwhit]

None of the pots have any effect on my bypassed signal, which I believe is a good sign. I'll get pictures tonight and post them, but I'm leaning towards making it true bypass

Yep, that is a good sign.  If you want to post your IC voltages, too, that never hurts.

[grwadley]

Found my issue today using an audio probe. I accidentally used a 100pf Ceramic cap I had ordered for my Moodring build instead of the 100n film in C1. Thus I had the volume drop for both bypassed and non-bypass stages, but the volume pot allowed me to ignore it while it was turned on.

[mgwhit]

That will do it every time.  Glad you found the problem.  Have fun!