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Oh I see, you don’t have a mono source on your iPad, or a situation where just discarding Left or Right is acceptable.

Yeah. It’s entirely possible this doesn’t matter, but I’d have to check if the apps I’m using (an electric keyboard app, a synth one, and Audiobus to mix everything together) have a stereo or mono out. Still though, I’ve already got some components in the cart and absent a guitar I need to work on, I have incepted myself into a project.

defendyachtrock wrote: Tue Apr 01, 2025 12:25 pm I’d have to check if the apps I’m using (an electric keyboard app, a synth one, and Audiobus to mix everything together) have a stereo or mono out.

Could you not use a plugin like DFX Monomaker?

The cheapest thing is probably figuring out how to get a mono or hard-panned signal out of the iPad, using a 1/8" TRS —> 2x 1/4" TS cable, and just ignoring one of the 1/4" cables (cut it off and heat shrink it even).

The prosumer solution is something like the behringer micromix or any other $50 4:1 line level mixer you can rustle up. It'll be useful for a bunch of stuff aside from this one thing so probably worth the minimal outlay of cashola.

Nate Dort wrote: Tue Mar 25, 2025 5:49 am

Frankie99 wrote: Mon Mar 24, 2025 10:04 pm Would this be an appropriate replacement for the 2 big caps in my Mark 3?

https://www.amplifiedparts.com/products ... ectrolytic

Here's a link to the schematic.

https://el34world.com/charts/Schematics ... manual.pdf

Yes, that 50/50 @ 500V dual will replace the original 40/40 @ 400V Mallory duals (there's two duals in there). You'll just need to figure out a good way to mount them inside the chassis. This usually requires drilling out the rivets that are holding the originals and getting some sort of large plastic strap with a screw and nut.

Or, do what this guy did and stuff new caps inside the old shells: http://russelltechnologies.co.uk/traynor.ygl3.html
*don't actually do this, it's a bad idea for a number of reasons*

So an interesting but long story made me abandon plans to work with the amp tech - my fault, not his.

At any rate, I opened mine up and best I can tell this is factory, untouched. Also got a really nice copy of the schematic, both below.

Am I to understand that there are only the 2 filter caps that need to be discharged and that I would replace one for one with the 500V, 50/50μF caps linked to above?

Links to larger images and previews below

https://i.ibb.co/vxQmFrc1/IMG-1676.jpg

https://i.ibb.co/vxQmFrc1/IMG-1678.jpg

posting for a friend here.

he said that he’s working on his 59’ Bassman Reissue (the 4x10 tweed one from the early 2000s) and he says that he can’t find the bias pot for the tubes. i told him that i thought that maybe it *doesn’t* have a bias pot, but I’m also not 100% sure.

anyone know the answer here?

Yep, it's fixed bias. If they want easily adjustable bias, it'll need to be modded.

Frankie99 wrote: Sat Apr 05, 2025 6:42 pm
Am I to understand that there are only the 2 filter caps that need to be discharged and that I would replace one for one with the 500V, 50/50μF caps linked to above?

The two big cardboard Mallory tubes are the two filter caps (well, four, really... there's two capacitors inside each can, but that's semantics) you need to disharge and replace. The good news is that those metal straps look like they're secured to the chassis with philips-head screws, not rivets, which means you could potentially reuse them.

If it were me, and I already had the thing opened up and the iron hot, I'd replace the other electrolytic caps (the light-blue ones on the board). Looks like there's about 10 of them that I can see. Those things really only have a useful life of about 10 years.

Cool thank you - I'm going to have a go at the filter caps tonight and order the remainder.

I ordered a couple of mounting brackets based on your recommendation and yes, I think I can finagle something that will keep the new guys nice and secure so thanks for that as well....

Installed the new filter caps today - I would take a gut shot, but I'm afraid y'all will start a side chat making fun of my soldering/silicon skillz.

I fastened 2 vertical mounts to the chassis horizontally, siliconed those where the OG caps were, installed, made sure there was room to remove in the future if needed and wired it up. It turned on, the fan turned on and everything lit up. I don't have a cabinet at home, so I'll run up to the space tonight and see if that did the trick.

Thanks for the assistance y'all.