Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TIMBO on July 10, 2013, 03:00:41 am
-
Hi guy's, The jubilee got a workout last weekend and I was able to hear the marshall qualities ring out in a large open shed by a guy that really knows his way around a guitar. :worthy1:
BUT, Too much distortion.....
He liked the clean channel and even liked it dialled to max.
But when in OD channel it was too distorted for his style of playing.
I've looked for a mod that could be done to the clipping circuit but the only one that I could find is just to remove the two LEDs and maybe remove the 10uf bypass cap on V1b
The idea of having a foot switchable Clean/OD is great
Any thoughts on TAMING the LEAD MASTER circuit.Thanks
-
(Tell him to buy his own amp, the beast spirit should not be broken, because you will need that fury or else you would not have brought the beast home.. :worthy1:
More cowbell!!! :l2:)
Now this is what I was thinking in my head when I read this, but seriously consider duel amps one for the clean tone and with a foot switch, bring the thunder...There I go again. I just think you will take the punch out of that amp once you curb that amount of gain you get from it..
I'm reading a good book by Merlin Blencowe: Designing Tube Preamps for Guitar and Bass who explains about every modification that you can imagine based on the sound you are looking for from your amp and how to get it, but I'm only halfway through this book. Your on the perfect forum for great modification ideas and people with the knowledge to help you make that happen.
Now don't stop playing until someone pulls the circuit breaker....
-
Thanks Custom, I like the amp as it is but there could be two more builds for me if I can keep the clean as is and only have a slightly dirty OD
-
I've looked for a mod that could be done to the clipping circuit but the only one that I could find is just to remove the two LEDs and maybe remove the 10uf bypass cap on V1b
That's a reasonable approach. Maybe reduce the 10uf to 2.2uf or put it on a switch?
With respect, Tubenit
-
Hi guys, I put in a DPDT switch in that will bypass the diodes and at the same switch out the 10uf bypass cap this really opens up the amp and gives pure overdriven preamp distortion and sounds AWSOME. I will mount the switch on the back and leave it as a manual switch only.
It has made the OD much louder where as both channels could be dialled in to similar levels but that is ok.
If an amp was to be built without the diode circuit would the 47k resistor after the .022 cap be required?? as it sounds fine as I have it drawn.
Can anyone see any problems with the LEAD MASTER pot connected directly to the .022 cap and grounded out when in CLEAN. Thanks