Here I will give you a deep inside, how i have done a rewind of the JTM 45 OT (Drake 784-103) for a Swiss customer after a break down of the first primary. As you can see, it is a very old transformer but following the descriptions of its owner, one with this unbelievable sound.

The first steps were to disassemble the core of the transformer in a right way by not heating it up to avoid any stress to the laminations. This is the most important thing, because dforming the lamination, even in the smallest way, will destroy the original magnetical structure in it and it won´t work any longer in the way asit has done before. Heating up the transformer will be a stress to the laminations too. After some experiments with some solvents I´m using three different items and mix them up. After one day, the laminations will fall out by itsself.

One other myth for good sounding transformer will end in smoke by looking at the pictures too. Not a few oppinions are saying, that only red enammeled copper wire in coils sounds good. This one has had like many others a nature enamelled one. Using the right enamelling will have an effect on tone too.

But here are now the pictures: