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Help on cab/amp switcher

PostPosted: Sun Jan 17, 2016 9:20 am
by JimSalabim
Hi!
I have two 50W tube amps and I want to connect them to a cabinet – only one amp at a time. The other amp should be connected to a 16 ohm dummy load at the same time (four 4 ohm power resistors in series, each 50 W).

Can I use a 4PDT toggle switch to do this and would it work as shown in my image?
Of course I would switch both amps to standby while flipping the 4PDT switch.
Image

Re: Help on cab/amp switcher

PostPosted: Sun Jan 17, 2016 5:03 pm
by Geek
Looks good!

Suitable switches I have used for such are the Digikey part number SC1821-ND (Mouser 502-50212LX),

Toggles are easier to mount, but I find the slides easier to work with hooking up with that many wires behind it.

Cheers!

Re: Help on cab/amp switcher

PostPosted: Sun Jan 17, 2016 5:36 pm
by JimSalabim
Thanks! I am just a bit worried about the few milliseconds between one set of contacts opening and the other closing on the dummy load, so one or both amps will be open circuited.

Maybe I could relays instead, like this, but with 4 relays instead of 2 then.
Image

Or could this be a problem because of the 1/2 second when the same loads are active on both amps then? (???)

Re: Help on cab/amp switcher

PostPosted: Mon Jan 18, 2016 4:12 am
by Geek
JimSalabim wrote:I am just a bit worried about the few milliseconds between one set of contacts opening and the other closing on the dummy load, so one or both amps will be open circuited.


Amps aren't delicate. mS won't do anything.

But if you're really that concerned, use a MBB (Make Before Break) contact switch.

Cheers!