Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: dogburn on June 28, 2025, 07:05:41 pm
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I'm modding/building a Champ type amp to use a 6AQ5 tube, and ordered a 7 pin socket from Amplified Parts/Antique Electronic Supply. The mounting ring it comes with is a separate piece, presumably so you can mount it inside or outside the chassis - but my question is how am I supposed to secure the mounting ring to the socket? No directions included on the website or with the socket. Should I use whatever adhesive will bond metal to ceramic? I've got E6000, which is the thing I'm inclined to use, but would like to know if that's the wrong way to go or if anyone knows a better way to do this.
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The socket should sandwich between the mounting ring and chassis. So the chassis hole must not be too big so only the small part of the socket can fit through, not the larger flange.
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Thanks! That makes sense. Of course, now I realize I have another problem, because the existing mounting hole was for a 9-pin socket, so it's larger than the 7-pin socket size and I can't do the sandwich thing. My fault for not realizing 7-pin sockets were even smaller (though to be fair, they do not come up in discussion very often).
Anyway, I'm going to have to find yet another solution now. Searching around, I see that Angela Instruments has an adapter plate that would work. Does anyone else carry such things? Alternatively, I've got pieces of metal and could possibly make an adapter myself, but I've got too many chores on my plate already.
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I don’t know of any other specific adapters. Hoffman sells a blocker plate for his Stout chassis but you’d still need to drill a hole in the plate for the 7-pin socket.
https://hoffmanamps.com/MyStore/perlshop.cgi?ACTION=enter&template&thispage=MiscHardware&ORDER_ID=!ORDERID! (https://hoffmanamps.com/MyStore/perlshop.cgi?ACTION=enter&template&thispage=MiscHardware&ORDER_ID=!ORDERID!)
If metal work was proving too tedious you could use some eyelet/turret board material to make the adapter plate instead if you had thick enough board. Maybe could even get away with some larger diameter washers to catch the the flange but if the sockets are ceramic they’re easy to chip if they get point loaded.
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Searching around, I see that Angela Instruments has an adapter plate that would work.
I looked at that plate - should work fine - better than trying to Mickey Mouse it.
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I think that plate from Angela is the way I'll go. I could craft something like it on my own, but it would be a pain in the ass, and I'm ready to finish this project.
By the way, I made a temporary fix to be able to install a 6AQ5 and test it out. It sounds great and all the mods work. Like I mentioned, it's based on a tweed Champ, with a 6AQ5 instead of a 6V6 power tube. I used a toroidal PT and SS rectification and added a switchable tone control (a la 5F2a Princeton). Plus switchable negative feedback and switchable cathode bypass for V1a.
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You want these! (https://www.ebay.com/itm/135868805097?_skw=ceramic+7pin+tube+socket&itmmeta=01JYZGDW0PY6FV0BME6CZDT5ER&hash=item1fa2696fe9:g:y24AAOSwxaRm5bsX&itmprp=enc%3AAQAKAAAA8FkggFvd1GGDu0w3yXCmi1fP1C9adZcdr917ILtFVYSRXRKhQK3KmsQcWqSXUbbbDvAon1ce7bD%2BO953d38DyeSDaYmEIs0KF2%2F4pKVX3wlZVZJ4%2BtimXacda5VQC%2BiVM2x2BaPlkDlSSoyFvlRltcUv3LPslw%2BAYcZw%2FdCLKf%2Blbqv3QlTpJKBqXVVaPEhD8x0JLXd6sqMOlWGqns0EXKcRM20B3puiEm3fkosSUvbEdVuEvbVZVwn3uyX80CI%2BCEWZH%2Fi6amI5UkioJHC94vKatqEfmz8g%2FGBsDGuE%2FVDnB6NE5%2F3XaRJjPLNWfkb%2BpA%3D%3D%7Ctkp%3ABk9SR8bAt_D3ZQ) - Best 7 pin power tube sockets available.
--Pete
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Congrats on the build. 6AQ5s are nice tubes IMO. They are also very good in low power push-pull amps.