I'm now really liking the clean channel of my Peavey c30 when the amp is cranked full wide open....but I would like the clean channel to distort a bit early than it does to give me more breakup....without using a pedal.
So, any ideas of what tubes to replace and with what to do this?
The way I understand it, to achieve this, a grade of power tube that is rated hotter would be the way to roll. It would take a re-biasing obviously. I think DBM did that with his Hot Rod. He might be one to ask also. A lot of tube suppliers can hook you up with tubes that are rated with a hotter voltage.
Dearthian: — May 16, 2010The way I understand it, to achieve this, a grade of power tube that is rated hotter would be the way to roll. It would take a re-biasing obviously. I think DBM did that with his Hot Rod. He might be one to ask also. A lot of tube suppliers can hook you up with tubes that are rated with a hotter voltage.
I did read somewhere that there is not bias adjustment pot in the C30 in that it is "self biasing", don't understand how that could be though ?
Edit: I wonder what it would sound like if I put a voltage dropper on the mains input to lower the operating voltage (like a variac) ???
Jon,
this is a tough question to answer. You can't do what Chris said because the amp is cathode biased. You need to buy matched tubes and the bias is set. In multi gain stage amps, I'd say get a hotter V1, but in this instance, that would just make it louder at any given volume setting. Since it's more breakup you want, my suggestion is to slam V1 with an OD or a boost pedal. If you don't want to change the tone or character at all, a boost is the way. But some boost do change it in a very positive way (depending on what you are after, as some add compression, some harmonics, and some even tone controls).
The other thing you can do, is experiment with the OD channel instead, and see if between the two controls it has you can get closer to what you want at a lower volume.
Yea, I didn't realize that about fixed bias. OD or clean booster is going to be the way to go.
What Howie Said. ;)
Yes I have the bbe clean boost which works well but I am trying to find a way to do this without pedals
I did find an article about pulling the two outside tubes but I will need to put a dummy tibe in those sockets as the filaments are wired in series
You could drop the value of the first preamp tube (12AX7) cathode resistor from 1.5K to 820 ohms. That'll give the stage quite a bit more gain and drive the stages behind it a bit harder. This is what Bad Cat does on some of their "hotter" amps to give more distortion to the preamp. That said, you're going to get a LOT more distortion when you kick in the gain boost, as well.
Dar