Active/Passive switch?

[Will_White]

So I am working on designing a bass with three pickups with individually buffered volumes and tones, (that's three active preamp buffers) I have all of the wiring figured out except for an active/passive switch in case the batteries go dead in the middle of a gig, preferably, I would have it go three volumes in passive mode, but I suspect that this would require a switch that is either prohibitively expensive, or doesn't exist, so I would settle for just the middle pickup volume and tone.

 

[line6man]

It can be done with a four pole switch. One pole for each pickup, and one pole to switch the output.

 

[Will_White]

It can be done with a four pole switch. One pole for each pickup, and one pole to switch the output.

That's a 4 pole 2 position on-on switch? With three poles wired as standard active passive switches like this
Link Removed
and how would I switch the output?

 

[line6man]

That's a 4 pole 2 position on-on switch? With three poles wired as standard active passive switches like this
Link Removed
and how would I switch the output?

That is a horrible diagram! The input of the preamp remains connected to the circuit in passive mode, causing an impedance drop that loads on the circuit. Proper active/passive switching is done with two poles; one for the input, and one for the output. In your case, there are four poles, because you have one for the output, and one for each of the three inputs. You will need a 4PDT On/On switch. I'll draw a diagram when I get around to it.

 

[Will_White]

That is a horrible diagram! The input of the preamp remains connected to the circuit in passive mode, causing an impedance drop that loads on the circuit. Proper active/passive switching is done with two poles; one for the input, and one for the output. In your case, there are four poles, because you have one for the output, and one for each of the three inputs. You will need a 4PDT On/On switch. I'll draw a diagram when I get around to it.

Ok thank you, there's no rush, I just needed to figure out if it was feasible or not

 

[line6man]

Here's your diagram, assuming separate "passive only" volume pots. If you want the same pots for active and passive, then you can join all four wires that go to the pots, and put the volume pots between the pickups and the switch.

 

[Will_White]

Here's your diagram, assuming separate "passive only" volume pots. If you want the same pots for active and passive, then you can join all four wires that go to the pots, and put the volume pots between the pickups and the switch.

Thank you that will work great