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on/off/on switch for bright/bold?

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I'm interested in adding a bright/normal/bold switch to my guitar amp, but am unsure of what switch is needed.

The switch would do the following:
Up = bright, connect a bright cap across the volume pot
Middle = normal, no connections (open for both)
Down = bold, connect a .68µF cathode bypass cap to the first preamp stage

I'm pretty certain that I'd need one of these DPDT switches

On/Off/On
http://www.mojomusicalsupply.com/item.asp?pid=84455&pg=13797&id=4110505

On/On/On
http://www.mojomusicalsupply.com/item.asp?pid=84457&pg=13797&id=4110510

Does someone have the schematics for both of these?
Which is the correct one for what I want to do?

Thanks!

Here's a photo
An externally hosted image should be here but it was not working when we last tested it.
 
The on-off-on is the type you want. Keep the switch close to the volume control - will pick up hum.

The on/on/on type is also callled "alternate action" - one of the poles changes state in the middle position, and neither is ever open. These can be wired as a 1 pole 3-way selector if you ever need one.
 
PRNDL said:
Does an on-off-on work by connecting the center to either the top or bottom lug, and no connection in the middle?

Perzakly. An on-off-on is the type I used in a project to switch the cathode current meter between left and right. The center position disconnects the meter completely in case of hum pick-up. So far, that hasn't been a problem, but leaving the meter connected isn't real exciting either since the current doesn't change.
 
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