The Mig amps ran their power tubes at pretty high B+... like 550v-600v.
This Hammond PT, at 120vac and with a standard FW rectifier using 50uF-100uF worth of high voltage filter caps, will be somewhere around +900vdc! That is unloaded of course.
However, if you buy a good, 5-8Hy +300-400ma choke, or two 4Hy +300ma chokes in series, you could put the choke (s) right after the cathodes of the FW rectifier, followed by a 15-25 watt 47 ohm power resistor... and have somewhere around +595vdc... which any good set of EL34s should be able to handle with proper bias.
But, I'd even consider using a high wattage zener diode, or string of diodes, (in series with the anodes of the FW rectifier to ground) to lower it down a little more.
With those trannys I bet this thing could hit 130-150watts output using four EL34s.
This Hammond PT, at 120vac and with a standard FW rectifier using 50uF-100uF worth of high voltage filter caps, will be somewhere around +900vdc! That is unloaded of course.
However, if you buy a good, 5-8Hy +300-400ma choke, or two 4Hy +300ma chokes in series, you could put the choke (s) right after the cathodes of the FW rectifier, followed by a 15-25 watt 47 ohm power resistor... and have somewhere around +595vdc... which any good set of EL34s should be able to handle with proper bias.
But, I'd even consider using a high wattage zener diode, or string of diodes, (in series with the anodes of the FW rectifier to ground) to lower it down a little more.
With those trannys I bet this thing could hit 130-150watts output using four EL34s.
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