I am building the amp out of the first edition of Hunter’s book where he uses an impedance switch with the two speaker setup. The parts list leaves something to be desired when it comes to clarity for a newbie. The list calls for a “heavy duty SPDT or DPDT using half.” The only switch I was able to find that sort of sounds like this was from Antique Electronic Supply and it is a Mini Carling 2 position SPDT (2A 250V, 5A 125V). Will this work? And if not, do I need it? I am only going to be using one power tube.
Hi Jordan, I use the carling switch for that, Antique Electronics # P-H494, You might also consider a Carling 3 position switch P-H520 to add a Mute/Standby function to the On/Off switch. It’s a great way to add that switching option without having to drill another hole in the chassis and adding another switch.
Hi there, I had a similar challenge when putting in a multi-tap OT (4/8/16).
To make life easy for me, I wanted 3 jack sockets on the rear, where whatever speaker was being used, could simply plug into the relevant socket, with no switches to flick. The NFB loop caused the problems.
I sorted it by using switched jack sockets that “made” a seperate connection when the jack plug was inserted, thus utilising the NFB, but only on the relevant OT tap. Works fine.