The gas regulator tube thing is charmingly obsolete; if you're just looking for a visual goodie to light up, fine. They really can't regulate any significant current to speak of. The octals should not be handling above about 30 mils or they start to get life-shorteningly hot. They are/were almost always used (in tube power supplies) to regulate a little tube (typ 6AU6, 6GH6, 12AX7) whose output gates a bigger tube. (6AV5, 6L6, 5881, 6080, 6550, 2A3) For more precision, 5651 tubes were used which for some reason (possibly mfg tolerances, maybe the smaller cathode to plate distance) operated in a much tighter range than an everyday 0D3 or whatever.
One nice thing about industrial gear, as you've said, is that there is not the obsession to cut 2 cents out of mfg costs, like there was with cheapo record players and tape recs. Costs were furiously attacked and consumers must have been absolutely obsessed with prices. I have a 1964 Martin guitar price list. In that list, IIRC, an O-18 was $255, an OO-18 was $260, a OOO-18 was $265 and a D-18 was $270. The idea that one would buy an O-18 over a D-18 for a $10 or $15 price savings sounds completely absurd. (I have 2 brothers, one bought a new D-18 in 1961 and the other bot a new O-18 in 1961)
And I acknowledge, these things can certainly change over time. In the 70's and 80's Deluxe and Princeton Reverbs were simply disdained, hated. Every single music store, it seemed, had a sad and lonely $125 Deluxe Reverb for sale that sat there for years. You had to have a Twin, and if you only had a Bandmaster or Bassman you had to go to an amp guru, have him rip out the trannies, install 2 add'l 6L6 tubes and Twin iron and SS rectifier. Nowadays....if you wanted to trade for a BF or SF Deluxe, it would probably take you 2 qty Twin reverbs!
In your situation, here is probably what *I* would do: I would build a single channel 6G9 Tremolux, the early version that used 6BQ5s.
http://el34world.com/charts/Schematics/files/fender/Fender_tremolux_6g9_d-fa.pdf If you don't care about Trem, lose the trem oscillator tube. I would strip one of the turret boards you have and build it on that.
However, that design still wants close to 400 volts on the 6BQ5 plates and you either have that or you don't. >>This is certainly one of the biggest "ooops" of used tube junk: Except for TV sets, you will very often find that the power supply (meaning the power transformer) can't get over low 300 volts.
If it can't, it can't, you can stare at it all day.
Some folks here like the VOX AC-30. I once had one of those and it was a fantastic amp, but the parts count in a VOX is huge.
Anyway, the Tremolux parts board is going to be virtually the same as some other build which drives 6L6 if that is your overall preference. So, if you build that and it doesn't do it for you, you can at least keep the built-up parts board and find an octal-tube amp you like better.
Before getting involved in a multi-every-which-way switchable amp, get a few simple builds under your belt. That, I would strongly advise.
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Topic: favorite old gear to buy for parts (Read 214082 times)