Upgrade MojoTone to Mercury Magnetics?

[agedhorse]

Andy, can transformers be made the same way as in the 50's or are there materials and/or practices that no longer meet EPA approval?
For that matter, has UL and other sanctioning bodies changed safety regulations / applications that would also potnetialy change tone?

Yes and no (for output transformers). Paper is no longer an acceptable insulation material under the newer safety standards, but paper is necessary for the (stick) winding process to keep the wires in place and to mechanically buffer the layers. Now, a very thin layer of Mylar is used in conjunction with the paper wherever insulation is required. The safe temperature ratings are also higher.

Also, the wire coatings are (much) improved, the impregnating material is an epoxy resin rather than solvent based varnish, it's applied using a VPI process (not just dipped) and the clearance/creepage margins are much greater now.

The manufacturing process is the same however, the same machinery and labor processes.

Does this change the sound of the parts? Yes, a little bit, BUT when the design is done to achieve similar results, any differences are so small as to be buried well within the tolerances of the materials themselves. The differences I have experienced have been the kinds of things cork sniffers argue about over identical part numbers and almost fabricated differences just for argument sake (or sport).

The output transformers designed to the newest safety standards are the safest, most robust, reliable parts ever.

 

[PhatBottomBass1]

I know that the Mercury Magnetics in this HW200B sounded very nice, had a beautiful red finish and were no heavier than any comparable transformer in its class. So, I say, "it is better to look good than to feel good", but in this case, you can do both if you can afford to do so.