stevehoover wrote:
I need help figuring out how to circuit a switch between parallel and single triode operation on V1. Currently the amp is wired with separate runs from the jack all the way to the triode, Hi 1,2,3 Low 6,7,8, and the three appropriate jumpers. I was also wondering if anyone has a way to rewire or trick the cliff jacks to turn on the second triode and still have a high and low input. I don't mind installing a switch ...but I promised my self this build would not be a switch fest like my last project. LOL.
The 18W Lite II series of amps has its guitar jacks set up, so that the "Hi" input gives you both triodes in parallel, while the "Lo" input gives just a single triode. Furthermore, if a buddy drops round and you want an impromptu jam, a guitar can be plugged into each input jack, and each will get its own dedicated single triode input. I don't know if it's exactly what you're looking for, but it's pretty darn cool all the same.
These drawings should show how the jacks need to be wired:
www.18watt.com/modules.php?name=Downloa ... it&lid=141
www.18watt.com/storage/18w%20lite%20II% ... ttilio.jpg
This particular design doesn't have the usual grid blocking resistors on the inputs, but you can easily add them in if you want, preferably soldered directly to the grid pins of V1's socket. You can use any value you like in the 10k to 68k range. 68k is more vintage authentic, while 10k lets in a bit more of the the guitar's higher frequency sparkle.
HTH