Safe to use simple DPDT foot switch as speaker A/B switch?

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pullshocks
Posts: 158
Joined: Thu Feb 16, 2006 3:42 am
Location: Seattle

Safe to use simple DPDT foot switch as speaker A/B switch?

Post by pullshocks »

I have a few drivers on hand to try out, and I find that putting the guitar down, switching to standby and manually unplugging speaker A, plugging in speaker b, etc, etc kind of "spoils the mood"

This got me thinking of an a/B switch.

From a psychoacoustic stand point, I know the louder driver will typically sound better. at least in the hifi world where loudness matching would be incorporated in the switching.

But would this switching pose any issue for the amp? Momentary no load condition? Other effects?
greenbottle
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Joined: Mon Dec 29, 2008 3:29 am
Location: Grafton NSW Australia

Re: Safe to use simple DPDT foot switch as speaker A/B switch?

Post by greenbottle »

Put a 270 ohm 5 watt resistor across the output of the output transformer.

Highest impeadance to ground. 270 ohms in parallel will have negligible on the speaker and protects transformer when there is no load(either switching or forgeting to plug speaker in before turning amp on: not that any one of us would do such a thing but does help to protect you from other people)

Alan
TheHandsomeOrk
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Joined: Sun Jun 07, 2009 2:43 pm

Re: Safe to use simple DPDT foot switch as speaker A/B switch?

Post by TheHandsomeOrk »

A simple stomp box type switcher can be made from the old headlight floor dip switch found in '60s cars. Still a few NOS can be found on ebay. Great for on the fly cab switching, big heavy duty clunky switch that can handle about 20 -30 amps.
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selloutrr
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Location: Southern California

Re: Safe to use simple DPDT foot switch as speaker A/B switch?

Post by selloutrr »

The new cheap small chineses switches will probably cause something to become damaged.

If you do add switching make sure you a heavy duty high Amp, High voltage switch that feels solid. Marine, and a military switches are often better built then what you can find over the counter at radio shack.
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pullshocks
Posts: 158
Joined: Thu Feb 16, 2006 3:42 am
Location: Seattle

Re: Safe to use simple DPDT foot switch as speaker A/B switch?

Post by pullshocks »

Thanks folks. I'll hold off until I can get a heavier duty switch. There's a place in town that has some.
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