1947 Supro

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billyz
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1947 Supro

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xtian
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Re: 1947 Supro

Post by xtian »

Wow, that's spanketey!
I build and repair tube amps. http://amps.monkeymatic.com
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Structo
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Re: 1947 Supro

Post by Structo »

Very cool! :D
Tom

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David Root
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Re: 1947 Supro

Post by David Root »

Don't see many in that condition. Looks like it's been under the bed since 1950!
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donzoid
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Re: 1947 Supro

Post by donzoid »

A very fine specimen!

Interesting that the field coil (if I read it right) acts as the choke in these amps. Is it quiet? I'll bet it sounds great.
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Colossal
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Re: 1947 Supro

Post by Colossal »

Holy smokes, that's a real beauty.
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billyz
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Re: 1947 Supro

Post by billyz »

I replaced the first filter, 40uf , with an internall axial. Replace all 6 of the wax coupling caps with nos cde greenies. one of the grid load resistors to the 6v6's was 6m instead of 250k. The other was 300k. At first I used 220k but then switched to 330k . I did not have 250k. I really like 330k in this paraphrase invertor. Sounding pretty sweet right now. Apparently most of these have a field coil but this one is an original jensen PM . The speaker frame is grounded too.
I'm kind of digging the pentode preamp.
Since I was soldering , I played with a 50uf bypass on the 6v6 cathode. It is a little smoother with the cap. Not really much difference in gain.
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