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Marshall mods or octal?

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Im still debaiting wether or not to get rid of my epi VJ v3 as it dont get played much at home.

Ive dont the bitmo trio mods and these certanly make it more versatile for me and now ive changed the preamp tube to a groove tube it sounds fat again right up to 3/4 volume then go's a bit pants :-


Anyhow i think id play it more if i was to do some more mods. I have other amps i can use so this would be my project amp over time if i keep it. Like i said i dont the bitmo mods now i wanna make it more marshally sounding. I know it'll never be a marshall but there are some good conversion to be done.


So what do i choose? Marshall mod or octal. Ive read up on the octal and it sounds like the best bet. Lots more work but everyone whos done it makes it sound good in there review.

Will these mods work with the bitmo mods i have already? Can i get schematics from sewatt? Will look there later.



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I've done both, and can recommend both. It really depends on what you're looking for, in terms of output. The front end voicing is pretty much the same. The difference is in the actually power output, and in the "girth" of the overall tone, with the larger bottle producing a much fatter tone and more power. I get just under 7.5 watts with mine, and it sounds astonishing. I wish I'd have done it long before I did. Even just the marshall mods with a real output transformer is a massive improvement over stock. You won't need the bitmo mods.

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Many of the "Marshall mod's" are already contained in the Ver3 amp's; since Epiphone listened closely to the forum here at one time.

There are a number of mod’s that can be changed especially the capacitors found in C3 & C4 locations,, much too fat at 22uf… They are best reduced to 2uf at best.. some even like them at .68uf for humbuckers (I find it too thin and have a 1uf and 2uf on a switch for each of these).

And put C5 up to 1000uf.

Do some reading on how to take voltages in the amp so your don’t un-bias the thing and strip the plates in the tubes.


Octal mod requires a lot more work but the change in tone will be different since it’s a completely different output tube.

Check Twangs most recent postings…


I have all the parts just sitting there to do the amp with a turret board, just have to put the guitar down for a few days and build it.. Maybe this summer


I'd put my efforts there if I were you.

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Cheers so far guys, I quite fancy going crazy and doing the octal mod but am unsure if i know enough to do it. Im a multi skilled engineer by trade so i know how to read schematics ect just want to obtain the correct info before i look at a parts list.

I think the octal sounds like fun. As i say it dont get played so the mods dont have to be quick something to plod on with.


So does it needs lots of parts for the octal? Can i use my origanal pcb or is it a complete rebuild with new board ect??

Will i need a new transformer ect?


Any help is great

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A number have used the orignal pcb board, there is nothing wrong with that tone wise.. with constant modd'ing though the traces won't stand up and will start to cause problems, that's why many have switched to turret boards.


you'll need a new 8pin octal socket, some wire around the 20ga size and a few new resistors for providing B+ voltage to the tube and bias resistor/cap and of course a screen grid resistor.


You would be best to learn the VJ schematic really well first, so when you read peoples posts you understand just in your mind what they are doing.. that goes along with just taking voltages from the amp.. know thy voltages like you can play mary had a little lamb.


head over to www.seawatt.com com read the FAQ's.. and learn first.


Once you can do those two things you're pretty much ready to go...

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I just built my first 6V6.. sounded way good.. and not at all like the el84.

and eracer is right.. not a lot of parts or cost to it.. but I did a new board .. I've had it with the stock ones, I just toss 'em out.

The cleans are way bigger, which I really like about it.

and the distortion seems crunchier to me.. less sand, more gravel I guess.


I haven't had a chance to really A/B my marshall head with the 6V6... I had a problem with a loose connection to cure so I didn't get much playing time.

But what I did hear I liked very much.



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