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Fork vs. Sleeve Terminal Octal Sockets.

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The appears to be basically two types of octal sockets out in the new/nos world - sockets with fork connectors and ones with a sleeve connection - which is best? The fork sockets I have have fairly high insertion force, tending to indicate that they might hold on to tubes fairly well Do they keep that grip over multiple insertions? US nos vs. Russian NOS (both fork and sleeve types) vs new Chinese?
 
I prefer the sleeve style sockets because the contact area is larger. But the fork type aren't too bad as long as they're NOS. And I only use NOS American. The Chicom stuff stinks. They soon loose their tension and grip. (Yet another example of a pretty copy with no substance.) Pay the extra dough for the good stuff. Tan mica filled for output tubes won't arc between pins easily from heat and age. And of course porcelain is great. I've no experience with the Rusky sockets, so I can't say.
 
hey-Hey!!!,
I have had good results with the Russian forks...even on an amp where I was swappiing tubes frequently.

I am not at all sure the sleeve type offers any better contact; I suspect that they're also riding on a few points. It is unlikely that they'd form a large contact area.
cheers,
Douglas
 
I've yet to break any of the cheapo fork type ceramic octal sockets I own. They do get a lot looser after you install and remove a valve a few times, though. I've got some sleeve type ceramic noval sockets as well, they do seem to hold the valve more firmly even after some use. Wow, now this post helped a lot, didn't it?

If I may, I'll ask if anyone has come across PCB mounted four pin sockets for 300Bs?
 
wrenchone said:
The appears to be basically two types of octal sockets out in the new/nos world - sockets with fork connectors and ones with a sleeve connection - which is best? The fork sockets I have have fairly high insertion force, tending to indicate that they might hold on to tubes fairly well Do they keep that grip over multiple insertions? US nos vs. Russian NOS (both fork and sleeve types) vs new Chinese?

My theory is that the forks have points inside that "dig in" with high force (as measured in pounds per square inch due to small surface area of the contact point) Is should make a gas tight seal from fork to pin tube. "gas tight" prevents corrosion of the contact area

Many guitar amps hang the tubes base up or horizontal and then put the amp in the same box as a speaker that is running at about a million decibles. The tubes seem to stay hanging in their sockets for years even when the equipment is moved on dollys down stairways. All of them I think use those old fork type sockets
 
I've built maybe 30 or so tube amps of all types and sizes and have been lucky enough to have on hand a few gallon ziploc bags full of vintage octal and minature sockets.

All types, brown phenolic ( sleeve-type), black plastic (fork-type) , and a few nice ceramic ones (fork-type). I like the brown sleeve type ,however if using them for something like a 5u4gb where you are only making 4 connections on the socket the tube can wobble. My only other complaint is that most if not all are bottom mount sockets, which makes it tough if you dont have the right size punch. Also, big base tubes like 6550 can hit screw heads preventing the tube from fully seating, So I've taken to using stainless rivets.

For the amps i build for myself i really like the pricy Belton fork-type, mica filled. I just love the look of them, and i've rolled countless tubes through them and they still grip well. Yes, they are expensive. So my vote is fork! or spork... well, if the tube fits...
 
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