Orange Rockerverb Preamp J201 Problems
Hello everyone,
happy to make my first post, sad because it starts with a problem.
I built an Orange Rockerverb Preamp based on the attached schematic from pcb mania. It's a relativly straight forward build using the Rockerverb preamp circuit and replacing the tubes with j201 jfets. I dialed the jfets to 4.5V and everything sounds fine.
However as soon as I play hard on the guitar the sound slowly starts distorting and finally cuts out completely.
I measured the voltage on Q1 and I can see that the voltages slowly rises to 9V while I play. After that the voltage stays consistent and can't be reduced with the pot anymore, till I short the jfet, decharging it.
After that everything works fine till I play, then it starts charging up again, distorting and cutting out.
I switched the pot and even the jfet but the problem remains. I'm using SMD J201.
Any clues what's causing this behavior?
happy to make my first post, sad because it starts with a problem.
I built an Orange Rockerverb Preamp based on the attached schematic from pcb mania. It's a relativly straight forward build using the Rockerverb preamp circuit and replacing the tubes with j201 jfets. I dialed the jfets to 4.5V and everything sounds fine.
However as soon as I play hard on the guitar the sound slowly starts distorting and finally cuts out completely.
I measured the voltage on Q1 and I can see that the voltages slowly rises to 9V while I play. After that the voltage stays consistent and can't be reduced with the pot anymore, till I short the jfet, decharging it.
After that everything works fine till I play, then it starts charging up again, distorting and cutting out.
I switched the pot and even the jfet but the problem remains. I'm using SMD J201.
Any clues what's causing this behavior?
- Manfred
- Tube Twister
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- The G
- Grease Monkey
Can go both before and after, just be sure it provides a DC path to the ground for the gate.. The tubes schematic has it after, but there are reasons for that (http://www.runoffgroove.com/fetzervalve.html).
I used a prototype pcb from pcb mania before it was public with an own BOM. If I remember correctly the values were the same like the ones in the schematic. I think the sound comes relativly near to the real preamp. Either way it works really good as a dirty overdrive . I think this one is a 1 to 1 copy of the original preamp circuit switching only the tubes for jfets.
What are the "0/1" and "1/1" pads between R5 and C5? I noticed that there is the same junction on the tube Rockerverb 50 mkII schematic that is attached to a SPDT relay. Is this where the clean/dirty channel switch would go?