Transformer Sources

[ErikH]

Calling all amp builders, fixer-uppers. Aside from Mercury Magnetics, what are some other good sources for replacement power and output transformers for Marshall amps?

I'm wanting to get mine back up and running soon but can't afford the cost of the transformer and labor to put it in all at once. So my idea is to get the replacement tranny, then save up to pay my tech to put it in. Ideally, I'd like the Marshall replacement. It's a 100 watt amp so I believe the stock tranny is a Dagnall.

 

[Rich_S]

Re: Transformer Sources

Well, Antique Electronic Supply has genuine Marshall replacements for $125 - $150, depending on whether you need a PT or OT. JCM900's use lay-down "Z-mount" transformers, so they are not as common as normal transformers for Plexi's, JMP's, and 800's. Most other places are going to have standup type, with a range of quality from generic replacements to high-end.

You could use a standup and mod it and/or the chassis. That might save you a few bucks.

However, you can save more money by skipping the tech. A transmformer (particularly an exact Marshall replacement) is no harder to install than a pickup. OK, it's a really big, heavy pickup, but still.....

 

[ErikH]

Re: Transformer Sources

Thanks, Rich. Is it just a matter of matching the wire colors? I've never done anything with amps so changing it myself is kind of intimidating. I do know for sure that I'd have to drain the filter caps before doing anything.

The one at Antique is not bad actually. Priced much less than other places and it's a direct replacement. The output transformer may be bad too. Won't know for sure until the PT is replaced and a load is put on it. That's what my tech told me anyway.

 

[muttonchopsrule]

Re: Transformer Sources

Thanks, Rich. Is it just a matter of matching the wire colors? I've never done anything with amps so changing it myself is kind of intimidating. I do know for sure that I'd have to drain the filter caps before doing anything.

i've never bought just a transformer before, but i would imagine that it would at least come with a schematic or diagram to tell you which wires go where. it's always helpful to have a multi-meter too so you can measure the voltages on each wire so you know for sure where it goes.

are we talking power transformers or output transformers?

if you can solder well, it shouldn't be too difficult to do yourself. just don't mix up any wires!! and yes, drain them caps!

 

[ErikH]

Re: Transformer Sources

Right now, just the power transformer needs to be replaced. There is a chance the output is gone too but I won't know that until the PT is replaced and a load is on it so it can be measured.

I can solder well, no problem there, and I have a meter. I've been soldering stuff since my teens, just not stuff like this. I need to make a cap draining tool too before I even attempt it.

 

[wixedmords]

Re: Transformer Sources

Good luck Erik. I know how attached you are to that amp.

 

[ErikH]

Re: Transformer Sources

Thanks, bro. Yeah, I love that thing. Don't get me wrong, the Vox is a great amp and I love playing it. But at the same time, sometimes I want that Marshall roar going on. I probably won't use it with a new project a friend and I are putting together, but just knowing that it works and I can use if need be is more comforting than looking at it now knowing that the PT is gone.

 

[wixedmords]

Re: Transformer Sources

Speaking of Marshall's, the new one is on their webpage. I saw it this morning while looking for pictures of JCM 600's.

I didn't get a change to look at the details. No time then, and gotta get out the door now.

 

[ErikH]

Re: Transformer Sources

Speaking of Marshall's, the new one is on their webpage. I saw it this morning while looking for pictures of JCM 600's.

I didn't get a change to look at the details. No time then, and gotta get out the door now.

Sweeet!!!! Can't wait to try that one out. JeffB started a thread too.

 

[gt5litre]

Re: Transformer Sources

You should check into Heyboer Transformers; used by the 18 Watt Amp Community and they do larger Marshall outputs too. Also check out Allen Amps he sells trannies that are made in the US and use M6 laminations and that gives you a better transformer with the best output response and run cooler as well which can give a trannie a longer life especially if you push it.

gt5litre

 

[Scott_F]

Re: Transformer Sources

check your pm's

 

[ErikH]

Re: Transformer Sources

Thanks for the help, guys. I'm hoping to have her up and running soon.

 

[kmcguitars]

Re: Transformer Sources

Another thumbs up for Antique Electronics. I sourced my Tranny's from them for my Homebrew. It's fair to say if you can wire up a PuP you can wire a tranny,BUT! I would add you should be a bit more methodical how you do it. Make sure your center tap is on a solid ground. (Some Fender and other amps use 2 100 ohm resistors to GRN. the CT.) This way the resistors bake, Not the tranny. Also I wouldn't worry about the export primary's ( Unless your planning a world tour?) I just shrunk wrapped em' and tucked them to the side.