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Topic: 12SJ7 tube based gear ? |
Bill Hatcher
From:
Atlanta Ga. USA
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Posted 4 Jul 2017 2:10 pm |
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i have a bunch of nice 12SJ7 glass bottle tubes. most of them you run across are metal. i use them for some old ampex gear i keep on the air.
anybody making any new guitar amps or preamps using these? or is there any vintage guitar amp stuff using this tube? like to try some of them out for guitar. thx! |
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J Fletcher
From:
London,Ont,Canada
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Posted 6 Jul 2017 11:22 am
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Hi Bill
I am not familiar with this tube, the fact that it needs a 12 volt heater supply would make it an unlikely choice for most musical instrument amps. |
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John Limbach
From:
Billings, Montana, USA
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Posted 6 Jul 2017 1:29 pm
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Heater voltage not a problem. If you have a grounded center-tap 6.3v filament winding on the power transformer, just lift the center tap off ground and 12.6v is right there.
Not sure of its suitability but it's a high gain pentode that should be good for something with the right choice of components.
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J Fletcher
From:
London,Ont,Canada
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Posted 6 Jul 2017 3:24 pm
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Hi
My point about the 12 volt heaters is that almost all tube musical instrument amps use 6 volt heater tubes.
The only ones I know that don't use series string heaters . I always thought that a 6 volt center tapped filament winding was a hum reduction idea. If you lift the grounded center tap how does that give you 12 volts? |
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Bill Hatcher
From:
Atlanta Ga. USA
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Posted 6 Jul 2017 3:57 pm
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the ampex 350 preamp was used on many hit records during the 1950s. its a great sounding unit! here is a pic. uses lots of 12SJ7 tubes!
also fender used the 6SJ7 in some early tweed amps. same tube, just different heater voltage. |
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Paul Arntson
From:
Washington, USA
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Posted 6 Jul 2017 4:23 pm
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Since it's a pentode you might be able to design a wicked tremolo with it using the extra grid as a gain control.
_________________
Excel D10 8&4, Supro 8, Regal resonator, Peavey Powerslide, homemade lap 12(a work in progress) |
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