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JTM45 build?

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Anyone here built a JTM45 clone before?

If so, are there any preferred layouts/circuits to use?

I have a Merren OT I ordered a while back, finally getting around to doing something with it.


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Metropoulos used to sell accurate JTM45 kits.  I envy you guys that can build amp without being zapped.
Were the Merren Marshall originals?

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Another vote for the Ceriatone solutions, they can build one for you just the way you want with a choice of tone caps in he preamp if you want to nitpick.  The C-tone lineup delivers the most bang for the buck along with the real deal tone sets for their circuits, they use great parts and do not cut any corners AT ALL in their pre built boards, kits, or built for me amps, I have 3 D-clones that have the C-magic inside.  Get one built with a simple interrupt fx loop in the build, will be there if you decide to use it.

Blah blah blah ,

take my word for it please,

saving you key spew...

mine do all sound amazing.

Research JTM 45, earliest ones ran 5881's through a not for guitar amp OT, the Radiospares.  Mercury Magnetics builds the Radiospares type in various configurations.  I have one of those Mercury 'Spares enhanced OT's in my Siegmund Blues Breaker JTM45 head with parallel tube fx loop.  That amp is king of the tone pile of all my amps including the D-clones with some real Tung Sol 5881's going into that enhanced 'Spares tranny with the 8.8k primary selected.  Besides the original, unicorn fx loop, that OT is a very big part of the reason why the Siggy sings like the fat lady closing out the show at the opera.  Nik at C-tone will say that his locally sourced at his spec OT iron for his JTM45 build is just as good as anyones, period, and he won't be way off at all.  His D-clone stuff has proven it for me.


Edited by 212Mavguy
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Thanks all!

I doubt I'll order a kit: just get the parts & build it. Thx for the tip on Ceriatone docs, I forgot about them. I had a Ceriatone DC30 & it was a fantastic amp.

Chris Merren hand builds his own transformers & is a longtime specialist on old Marshalls. He used to work for NASA & really knows his stuff. He also makes Neve, McIntosh, and Hiwatt replacement transformers:


I have one of his OT's in my '66 JTM100 and it's amazing. So I bought a JTM45 OT with intent to build one, at some point.

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