What type of toggle switch when driving with batteries?

[captain]

I'm in the process of designing a 3-channel LM4782 gainclone.
I'm going to power it with two 12-volt batteries connected in series.
Ground will be taken off the junction between the two batteries.

Now I'm trying to decide what kind of On/Off toggle switch for the front faceplate.

With a simple "single-pole" I could open and close the ground connection.
But, this would mean that the rails would still be in constant battery connection.
What would this do to the chip?

With a "double-pole" I could open and close the rails.
"Triple-pole" would open and close all three.

The real reason I'm asking this is that I also want to run an active cooling fan off of the same switch because I want to force the fan to be on when the amp is on.

Componding the issue is that the fan will have a high speed or low speed.
Now, this means the switch now has to become "double throw" with the fan occupying one of the available "poles" (giving a worst case total of 4 poles).

Switch Positions:
Up - amp On, fan on High.
Center - everything Off.
Down-amp On, fan on Low.

So, I know that "double throw" is needed.
But, I'm trying to determine if I can do "double pole" or "triple pole" rather than "quad pole".

I hope I've explained clearly...
I'm kind of new at this...

Thank you for any assistance.

[randytsuch]

I implemented a battery powered GC with a double pole, double throw switch.

And, do you really need a fan?

I never have any heat issues, with a reasonable size heat sink.

Good luck,

Randy

[jeff mai]

If you use a DPDT switch on the +/- rails, you may have to try several switches. The first one I used closed the two contacts at slightly different times resulting in a loud pop at the speakers. The next switch I tried was silent.