Marshall power transformer in Fender amp

[MrUnderwood08]

I am planning a build similar to %13 CJ11. The specs for the power transformer are 290-0-290 to use a GZ34/5AR4 and keep plate voltages in 5E3 range (360ish). I'll be using a blank chassis and cutting machining my own holes. Mercury Mag has a transformer that I think works (FTDP-M: 290-0-290 unloaded). Cheaper options are available but they are Marshall style transformers. Any reason I couldn't/shouldn't use a 18watt Marshall transformer. Orrientation of Power and Output transformers? Mounting style? I can't imagine that power transformer affects tone beyond supplying plate voltages in the correct range... Am I wrong?

Dan 

[jjasilli]

PT's (and certainly OT's) for music amps are wound differently than trannies for electrical tools, e.g.  Within the music world, especially for hi-fi, differences in tranny winding and the materials used, etc can be a holy grail.


IMHO any guitar amp PT that meets your voltage and current specs is fine.


I must say that on the part of Mercury Mag, "290-0-290 unloaded" is an incomplete & improper spec.  The voltage should be stated along with current draw.  We know it's for a Tweed Deluxe, so we can calculate the current draw.  But we still don't know how much that current draw will pull down the secondary voltage under load.  As a general rule of thumb (per Jack Darr) we can guess 10 - 15%.  Still, pretty sloppy for a reputable company.