Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TIMBO on October 03, 2021, 12:59:27 am
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Hi guys, Does such an animal exist.
Yeah I know just use half a 12a_7.........
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Hello my Friend
I didn't remembered about a single triode in noval pin envelope, but, after a search, seems it exists
see
EC86
PC88
6S3P
6S4P
6S19P
6S45P
you can find it here
https://tubes-store.com/index.php?cPath=103_104_110&page=2 (https://tubes-store.com/index.php?cPath=103_104_110&page=2)
I think I understand the reason for such a search
but I've a consideration for you
I think it will be way more easy for you to use an easy to be find a "standard" (12au7 - 12at7 - 12ax7 ... etc. etc.) 9 pin double triode (with specs conforming to your need) and abruptally go with parallel of the two triodes
other "easy" option is to build or purcase a 9 pin to 7 pin adaptor, there is plenty of fine single triode 7 pin tubes around
Franco
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Hey Franco,
Thanks for that info.
I have plenty of 6AV6 but got no 7 pin sockets.
Got plenty of 9 pin sockets.
I need an extra gain stage to drive the reverb in the 5E3
5E3 REVERB EXULED (el34world.com) (https://el34world.com/Forum/index.php?topic=27823.0)
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There's nothing shameful about only using one triode in a 12AX7. Leo did it! :wink:
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EC92 is half a 12AT7 but also 7pin.
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Hi Timbo
You could try an IRF820 Mosfet similar to attached pix (haven't done it myself but others have). Probably requires an isolated heatsink.
Alternatively fit a new 12AT7 to drive the reverb, as per Hoffman One Channel AB763 (very nice drive setup).
...and as Sluckey and Leo have done in the past, leave the 1/2 12AX7.
Kind regards
Mirek