- Occasional poster
- Posts: 497
- Joined: Fri 04/27/18 3:02 am
They are all different.
The Mojotone adapter is $3.50; it's shaped like a dog tag and has a 3/4" inner hole which a 9-pin socket fits into perfectly. The Tubeface one is $3.49; it's shaped like a doughnut, with an outer circular diameter of 1 7/8" and a concentric inner hole that's 7/8". The Burriss one is $9.95; it's shaped like an eccentric cam (football shaped), and has a centered inner hole that's, I dunno, way bigger than 3/4" but I'm not sure the exact diameter since I have never purchased one. It seems like the overbored models from Tubeface and Tube Depot must be designed for "through-chassis" mounting, where the tube slides through the chassis and into a board-mounted socket. The only points of physical contact on these are the mounting bolts. 12AX7s, EL84s, EZ81s, even the slightly fatter bottle Mullard CV4004s all slide easily completely through these overbored holes.
On the Mojotone adapter, the entire socket shoulder circumference rests against the adapter and so this seems to be the only one appropriate for properly supporting a chassis-mounted noval socket.