Toroidal power transformers in a tube amp

[txflood]

I had a question about toroidal power transformers. I have an EL-84 design tube amp that the original power supply transformer with 3 secondaries is cooked. I was thinking of replacing it with 2 transformers since I can't find an exact replacement that meets the specs. I was going to have one cover the high voltage and heater secondaries, the other would supply a 26V CT that is used by the +12V / -12V DC power section.

Would I be able to use 2 toroidal transformers as my replacements? It would be really cool to just stack them concentrically and run the leads, but I don't know enough about this style of xformer to know if this is going to lead to undesirable results. Any thoughts?

If this isn't a practical idea, would a single toroidal along with a conventional xformer (like a Hammond) be a good solution instead?

Thanks

 

[Eli Duttman]

IMO, the thing to remember about toroids is their wide bandwidth. Suppress crud riding on the AC mains by looping the primary leads around ferrite beads. Use chamfered beads, to avoid nicking wire insulation.

Make certain to take precautions against crush, when you assemble the trafo stack. Perhaps a thin plate washer sandwiched between 2X rubber washers is appropriate. Don't get frisky, when torquing the assembly down.

Stray magnetic fields in toroids is low, but using non-ferrous metal in the between trafos plate seems sensible to me.

 

[kevinkr]

Edcor can probably make what you need, however there is a one time set up charge unfortunately of $50 in addition to the single piece price.

There may be other transformer makers like Heyboer to consider.