Cipher wrote:Hi Duffy, I'm happy to see you find the photos useful.
I have replaced V1 and V2 preamp tubes, and all four power tubes. I used NOS Sylvania's in the preamp and there was a noticeable improvement. When I replaced the power tubes with E34L's, I set the bias on the cold side (78ma per side) and to my ears, this yielded another improvement, albeit not as much as the NOS preamp tubes provided. V1 & V2 were replaced because both of the factory tubes failed. The power tubes were replaced because one of the four was failing so I bought a matched quad and just replaced them all. If you are looking to improve the tone and perform a little preventative maintenance, the glass is good place to start. IMO.
The rest of the amp is all stock, including C19. I thought about clipping it, but keeping the Treb and Pres between 2-4 works for me. If I do anything with C19, it will be a value change, make the cap switchable, or maybe both.
Duffy wrote:I know a dude around here that makes amps and is highly regarded as a guitar and amp man. He isn't formally trained in the field, but obviously has a lot of real world expertise. Do you think I can trust him to put in the new tubes and bias the amp? Those were JJ E34L's, right? I have liked the electro harmonix preamp tubes in the past.
matt3310 wrote:I wonder if these need the ground mod on the speaker outputs, or did Marshall fix that on these?
Users browsing this forum: No registered users and 1 guest