🚀 go-pugleaf

Instead of worring about the tubes, the better question is, "where
can I find output transformers to handle 200 watts?"  From
experience, I know those will be difficult to find and expensive
when you do.  I found a few UTC "Ultralinear" transformers several
years ago at Fair Radio Sales.  I like the Williamson ultralinear
design with tetrodes.  6L6 derivative tubes are pretty good, as a
lot of output trnasformers are desinged with those in mind.  That
includes 6L6, 1614 metal envelope and KT-88s.  A pair of 6L6s is
good for driving about 30-40 watts.  Going up to 200 watts is probably
better done with industrial type tubes such ass 6550s or 6080s.
I picked up some Amperex 6L6 tubes at a hamfest last year to
replace the 1614s in a Macinthosh MC-30.  The Amperex tubes have a
very nice sound in the MC-30.

You'll have to go back to the 1950s and early 1960s to find much
useful literature.

I always thought it would be fun to make an audio amplifier out
of something like Eimac 4CX150 tubes.  The execution would be awful
since those tubes need somewhere around 1800 volts on the plate.
That would reqire a pretty exotic output transformer and forced air
cooling.  In fact, we used to have a 60 Hz to 400 Hz power
converter rated at several KW that used 4CX150s.  I think it had 8
tubes and a GIANT transformer.  It dated to about 1964, before
semiconductors that could handle those sorts of power levels were
affordable and/or reliable.

Unless you have tube nostalgia and/or want a PA for music performance
applications, I'd forget about making a tube power amplifier and
design with transistors.


-- 
Bill Mayhew      NEOUCOM Computer Services Department
Rootstown, OH  44272-9995  USA    phone: 216-325-2511
wtm@uhura.neoucom.edu (140.220.1.1)    146.580: N8WED