Higher PT voltage or different Rectifier?

[Ringwraith]

The Weber PT secondary in my 5E3 is 340-0-340, which I think falls in line with the "voltage corrected" PTs. The Mojo & Mercury FTDP PT's put out 385ish on the secondary which are suppose to be copied from original late 50's 5E3. I know there's the whole argument about which way to go but I'm curious & am going to try a higher rated PT just to see for myself which I like better. My question is however, if I put in a different rectifier, this also bumps up the B+ voltage. Would there be a difference in tone/feel etc from getting the higher B+ from the rectifier tube or a different PT??

Thanks
Sean

[Five_E35]

I believe a 5V4 rectifier can increase the voltage slightly, but people on here have also said the Russian 5Y3 isn't exactly a 5Y3 and puts out more voltage than it should. There was thread here about favorite 5E3 B+ volatges with a lot of usefull comments. Someone else tried a MM Toneclone and didn't like it. It's not known which Mercury PT Fender used, but the Fender schematic shows 370V B+.

The Weber 5E3 PT has a 125 volt primary, but there's also a 120 volt tap(brown wire on mine). I messed with mine and using the 120 volt connection at 120 VAC from a Variac, I'm getting 355-365 volts B+ with a NOS 5Y3WGT and various NOS 6V6GT's. Using the 125 volt wire(blue) drops the B+ by about 15-20 volts. The filament voltage also changes. Using the 120 volt connection at 120 actual it's up around 6.8 Volts, so using it that way if you also have high line voltage would likely put the filaments over the 6.93 volt maximum.

[MWJB]

The Mojo does NOT put out 385VAC (loaded) on the secondary, that's too much for a 5E3. With an NOS 5Y3 you should get <385vdc after the rectifier. Irrespective of PT/rectifier, if your plate to ground voltage is in excess of this, or you have more than 40mA per tube, think about larger cathode resistor (300-330ohms).

A lot of folks prefer a 5V4 rectifier for a tighter response, I would try this in the first instance (taking note of the previous paragraph).

FWIW I've seen 410vdc after the rectifier on a '60 Deluxe with the stock circuit & rectifier.

[Ringwraith]

What's the difference in tone/feel/response between attaining higher B+ from a higher PT or rectifier?? Or does it matter?

According to the specs Mojo sent me on their Tweed Deluxe PT, the secondary is 385-0-385.

Cheers
Sean

[MWJB]

My preference would be to use a PT that gives correct dc voltage after the rectifier (350-380vdc) with a NOS 5Y3. This way you get the classic 5E3 tone, with the correct recto, and have the opportunity to try a stiffer recto, like the 5V4, for a little more headroom/punch if required. If your amp is putting out well over 380vdc with a NOS 5Y3 then you probably need to rebias anyway...you may or may not have leeway to use 5V4, without going to a much bigger cathode resistor (which you don't really want to do).

The higher voltage with the 5Y3 will still compress the front of the note a little more than the same voltage with 5V4.

That's just my preference...some late 50's Deluxes really need a 330ohm cathode resistor anyway and sound fine, but if you are deciding things at the outset you may as well have a few options that will be afforded by the lower B+.

I have a Mojo 5E3 PT in an amp, I get 384v at the 6V6 plate (to ground) with a NOS 5Y3 & 250ohms at the cathode. It's always best to actually measure voltages in a working amp rather than take specs as gospel...specs are nominal. Some manufacturers give rectified dc voltage spec for one PT, but AC voltage for another, or even unloaded voltages (not much use). It can get a bit confusing.