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Hoffman Amps Forum image Author Topic: 5A3 preamp tube  (Read 1782 times)

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Offline Leevi

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5A3 preamp tube
« on: October 31, 2020, 05:28:20 am »
I'm going to build a Deluxe 5A3 based amp and have thought replace the 1'st preamp tube 6SC7 and PI with 6SL7s.
The specifications of those tubes are very similar, the biggest differences are on cathode and pin order.
I have even seen some schematic versions where the PI is replaced with 6SL7.

https://el34world.com/charts/Schematics/files/Fender/Fender_deluxe_5a3_schem.pdf

6SL7 is better available.


Do you think those replacements especially the 1'st tube will work fine?


/Leevi

Offline DummyLoad

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Re: 5A3 preamp tube
« Reply #1 on: October 31, 2020, 05:35:02 am »
shouldn't be any issues. IMO some of the 6SL7GT sound better than the 6SC7. 


--pete

Offline bmccowan

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Re: 5A3 preamp tube
« Reply #2 on: October 31, 2020, 03:51:43 pm »
I built a 5C3 with 6SL7s. worked out fine. It started out with grid leak bias, but after a while I changed the preamp to cathode bias. Both sounded good.
Mac
“To my surprise, when I opened my eyes, I was the victim of a great compromise.”
John Prine

 


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