they all do that. Seems to run fine without the wax. Ran mine 4 hours a day for about 9 years without the wax. 12 hours on weekends. 3 sets filter caps, 2 rectifier tubes, 2 sets output tubes in that time. Changed selenium bias rectifier once, then the 2nd time it went bad put in 1n4003's. Needed a resistor change with less resistance in 1n4003. 6CA7 became unavailable about 1979, started seeing them (EL34) in guitar shops about 2005 at 10x the price.
These go about $600 US on ebay "amp for repair or parts", ie not even working. *****y bogen PA tube amps are going for $100. I paid $100 for mine with a PAS2 preamp in 1970.
They allegedly have less distortion with a triple input tube board ala Marantz 7. I bought the board from classicvalve.ca but never installed it. Tubes are so expensive, and transistors are so cheap. ST120 or PV-4c uses less electricity, too.
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What price? I don't see one in any of the many posts.
It's an ST-70 - the 350 Chevy of the audio world. I was fortunate enough to have cut my DIY teeth on a handful of these and other Dynaco amps before they became a "thing". Fun to work on, and pretty bulletproof, but nothing to write home about.
Good luck with the sale.
I feel sarcasm in here...
At 700$ you also get the auto bias board for the EL34 that is brand new and costed me a little over 130$CAD with shipping, so pricing is more than fair...
Do
Every single st-70 seen on Craigslist or epay for the last few years is in the 650-750 range (regardless of upgrade or condition as long as it works) if you want to sit on it at 700 and wait for a Unicorn more power to you (I probably would too) but if you want to sell it before Christmas 2021 you might have to drop the price.....
That's why I said in the posts to make me an offer. I can't possibly know how much every places on the web sells for. I'm open to fair offers
Do
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