Potentiometer with ON/OFF switch?

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I was wondering if anyone knows where I can get a push-pull dual gang potentiometer?
I'm building a compact stereo amp so I'm trying to keep the part's number down to a minimum, and I thought that turning the amp on and off by the volume knob would be a cool idea.
I did find this online: Dual Gang Potentiometer, Audio Taper, with Push Pull Switch DPST 1/4 inch X 7/8 inch Shaft
But I'm a little uneasy about purchasing off random sites

Has anyone come across these before?
 
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I was wondering if anyone knows where I can get a push-pull dual gang potentiometer?
I'm building a compact stereo amp so I'm trying to keep the part's number down to a minimum

I'd avoid doing this if you can. It was routine in many older integrated amplifiers, but having 120VAC near
the audio is not a good idea. Also, the control wears out faster, and you can't use the very bottom
of the range, because the on/off function requires around 30 degrees of rotation. Good volume controls
just don't have this option.
 
More common as far as I know is where ON is achieved by turning the pot
toward the right hand side, and OFF hard to the Left. The Quad 33
as a preamp used such a switch on the volume control pot.

If the 10k ohm range and its taper, and type suits then you have already
found what you need.

You can always arrange less current to the switch function by making
the pot switch activate a relay coil and the relay then do the heavier
duty of turning on, however would require some small current DC circuitry
that is ON before the switch activates

Try the large stockists like Mouser Farnell RS and Digikey
they will have many choices for you.

Cheers / Chris
 
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I'd avoid doing this if you can. It was routine in many older integrated amplifiers, but having 120VAC near
the audio is not a good idea. Also, the control wears out faster, and you can't use the very bottom
of the range, because the on/off function requires around 30 degrees of rotation. Good volume controls
just don't have this option.

Besides wearing out faster, is there any sonic issue or health hazard with doing this?
 
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I'm specifically looking for a dual pot
Unless there's some way of using a regular single pot as a stereo volume knob?

It can be done...but its not easy... you don't want to go there ;)

Switched pots aren't the way to go in all this really. Use a separate mains on/off switch that's up to the job. Interrupting (switching) the current to a large power transformer can generate significant arcing at the switch contacts due to the large inductance of the primary winding.
 
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