Hey Patrick, you can do better than that!
Ah, well, probably I could, but I am a retired self taught amp-worker person who may have already published enough so that if anyone needed to known what I think, ( or that I think at all, or used to think, ) it could be gleamed by the fact I've not experimented with a whole range of amp topologies and stuck firmly to those that gave me good enough measurements better than most text books indicate is a good enough standard. I sold amps to ppl, and every amp I sold was different to the last, but had within it the same mental approach, and this for eg, did not include ISTs, because of their BW limitations, and THD injections to the signal path. I did allow myself to use of choke feed to driver stages, but always with a series resistance between end of choke and anode to isolate the ugly behavoir wound items can cause in audio amps.
You actually touched on the
reason that circuit does what it does in your response. And I’m
surprised that Phil has not chimed in with his ideas.
Well, perhaps he saw no mutual benefit in responding. The purpose of discussion groups sensibly conducted is that posters exercize their mind as well as readers. My experience here since 2001 has surely exercised my mind at least.
Here is a hint to give you a lead to the operation of the circuit. You
can find enough information in the RCA Tube Manual RC-14 to get you
going. Don’t think you will find much to help in RDH4.
RDH4 and all other books I have don't have your circuit you posted.
The IST has nothing to do with the circuit other then as a phase
invertor. It will run well from any common power amp front end. Even
your favourite. So go back & take another look!
OK, I will, but seems like triodes were like FB resistors, but I have to return to make sure. I've got 101 projects to complete - very happy now without audiophile customers to drive me broke and snd me insane.
Not much biking these days, altho I got out for a little more than 50 km
yesterday. Busy with the log splitter & otherwise getting the place
ready for winter. I will soon trade the bike for skis. The weather to
turn cold & snow this week.
Opposite here, warming up, early mornings good on bike, but have a bout of back trouble rite now. Maybe a week or two off bike, its always good to quit for a week or three each year when I have averaged 12,000km. I just have a house to care about, hedges, lawns, wysteria, and plumbing, draining, electrical et all -been 35 years since I needed to hire a tradesman, because I am one.
Not much electronix this summer either. Lots of yard work on 4 ½ acres.
Had to chop up five large trees that came down in storms. And the
electrical boxes I put way out in the yard after 35 years the wood was
shot. I put 110/220 volts underground the full length of the property
when we built here. Very handy, but lots to repair as everything seems
to wear out. Me too!!
I'm having a good run with my work with very few repairs needed, and am reaching the stage when house begins to fall down around me and I don't hafta give a **** about it, I ain't tryna keep up with the Jones's and I like frugality, fine music played live, bicycles, socially cheerful companions, and farnarcling around with primitive electronics, and the rest of the world is forgiven for their stern faced determination to make a lotta mistakes.
In the meantime, here is something else to get your mind around.
Yeah, The pear seems at ease with its connections. So few of them, wheras a bunch of grapes is needed to represent the carp in box of modern electro-junkery.
Patrick Turner.
John
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