Impedance selector switch

[rutledj]

Are there any specs that need to be followed (voltage or current) for a slide switch used as an speaker impedance selector switch? Will a typical 125v switch suffice (in a dumble clone)?

Thanks,
Rut

[rutledj]

Maybe I should ask it another way. If I'm using ohm's law correct then sq rt of P x R = V (assuming a 50 watt amp) 50w x 8 ohms = 20v.

I = P/V = 50w / 20v = 2.5 amps. Obviously this would vary some as the speaker impedance changes but would you say I'm close on this assumption or am I way off here?

[Mr. dB]

I suppose it would be important to know if the switch is shorting or not (break-before-make or make-before-break)?

[rutledj]

Not really sure to be honest. Just a simple slide switch. More concerned about the voltage\current handling capability than what happens when you change impedance.

[Mr. dB]

Blowing up the switch vs blowing up the amp?

[Heisenberg]

Putting a slide switch in could certainly increase the possibilities of two of the secondary windings touching together. Bad news bears.

There is a very good reason you don't see slide switches on any amplifier's impedance switch. Especially in a Dumble. Break before make or otherwise.