Recent content by Old BF Shred

I remember hearing that the Phase Inverter (driver) tube can cause this. I believe it is V7, but the manual will tell you for sure. Hope that helps. :)

Don’t own a Mark series amp, but just a shot....512v seems high.....6L6 is rated for 500. Yikes. Do you get any crackling/popping noise with it? May want to check balance (bleeder) resistors (150k, I think) across the primary caps. If these are not soldered well or open, that could explain...

I can’t really recommend any of those methods specifically for the Nomad, as I have not tried them. As you’ve done some mods yourself, I tend to assume you have, at least, a basic understanding of working on amps, including, of course, the dangers of working around high voltages. But...

That is the correct place. I'm not saying it will sound like you've engaged an overdrive...that is subjective, for sure. It does not really increase gain, except in the sense that it provides a bit more output to subsequent stages. I feel the Nomad has enough gain on tap, just lacking in ability...

You could try a 270 pf cap across the 100k resistor after V3a (between the .1u cap and ry4b on schematic). Did this with a friend's Nomad 55 and he loves the result. Of course it affects ch2 as well, but really helped ch3, giving it more 'bite' as well as volume.

I have had to do this on more than a couple of guitars. For some reason, the Schaller "type" of locks, that I've seen, always seem to come with screws smaller than the stock ones. It may hold at first, but eventually comes loose...not good. So...fill the hole with glue (like Titebond or =)...

Good score! You got a whole lotta amp for $800. Enjoy!

I imagine it could be re-coned. Comes with a new coil. Shop around and see if you can get the original or as high quality a substitute as you can. You want to preserve the original sound as closely as possible. I have seen a place on the web that offers re-cone kits you can install yourself...

I am guessing this is noticeably worse with a guitar/cable plugged in? The amp has reasonably good shielding and should block a lot of it, with no cables plugged in the input or loop. Not really familiar with the MV25, but the preamp tubes should have metal shielding cans on them. Most, anyway...

Good tips, KH. I found I had to experiment with various settings to get it to where I like it with my speaker cabs and FX devices, etc....and of course, YMMV. :wink: And, mind you, these settings are not necessarily what I run for every gig...depends on the set list... I was disappointed...

Are you looking to get a more "Marshall like" tone? Many folks seem to want to get that from a Stiletto. Never gonna be exactly like Marshall, but I found, at least for the Ace, this gets it closer: Bass, low...9 o'clock or less; Mid 11 - 1 o'clock; Treble, noon or less, maybe a lot less...

It would be a shame if it turned out to be just a bad tube or a dirty (often FX loop) jack or control (volume, tone, etc.) pot. But, though I hate to say it, you don't want to invest a lot just to end up returning it. GC "may" balk if they see evidence of someone having attempted to repair it...

I would not clean off the rust on the transformers, if I were you, (especially not with steel wool....) You are better off not disturbing the rust. You run the risk of shorting out the laminations (layers of metal the transformer coils are wound on). This can result in a condition that can...

Has it ever had the power supply capacitors replaced? They could be a bit weak after all this time. Although I have seen 40+ yr old amps where the old caps, after being replaced as a preventative measure, still measured good, at rated value. If you constantly played this amp, they could still...

I have not had a chance to try a V 35, but the Mesa website demos do sound different! Perhaps just a weak preamp tube that did not survive shipping. I don't recall you saying you had try to swap out any of them. Good luck!