Custom bass wiring help: Active/passive switch retaining passive tone

[basillio]

I am currently putting together a custom precision style bass and I want to have various tone controls.

I need help specifically with wiring the Active/passive switch as I have seen various wiring diagrams. I want to retain the passive tone knob and have a 3 way switch on the tone pot (2 different caps & pass through) into the preamp. But If I have an active/passive switch, will that kill everything? I have attached a diagram of my intended signal chain and the active/passive wiring.

Which active/passive wiring diagram is correct and what kind of switch will I need? on-on-on, on-off-off, etc.?

Parts: Seymour duncan SPB-1,Cts stacked pots (250k Vol./500k Tone), Seymour Duncan STC-2c-bo preamp, DPDT Switches. Thank you for your help!

 

[ABtheBassPlayer]

Both wiring diagrams are correct but are you planing on having the tone pot “on” all the time regardless if the preamp is engaged?

 

[basillio]

Yes, I would like it "on" at all times. That is why the I want to have a 3-way capacitor switch so that the middle one with no capacitor will basically be a psuedo tone bypass. Although I don't know what kind of switch I need or how to wire it. I have done a 2-way but not a 3-way cap switch.

would the active/passive switch at the end of the chain kill the whole circuit or just the preamp?

 

[4StringTheorist]

As shown, should work. Just a note, for the tone knob to be disabled, you're not connecting it directly "through" to ground. Rather, the lug that's normally connected to ground via a cap will just "float" and be connected to nothing. Removing the path to ground will make the tone knob inactive. I think that means you'd need a DPDT on-off-on type switch for that application.

 

[basillio]

Thanks 4stringtheorist & ABtheBassPlayer!

would an on-on-on work like in this diagram? Ignoring the "bass-cut"/"treble-cut" wording

 

[ABtheBassPlayer]

You’re going to need an On-On DPDT for the active/passive switch.

And an On-On-On like your diagram above or an On-Off-On like @4StringTheorist suggested for the Tone Cap.
Or another On-On if you don’t want to “disable” the tone pot and have one of the caps in the signal at all times.

As for the order of things, I think the better way would be to have the passive tone in the signal before the preamp.

 

[basillio]

Thanks guys, I have one last question.

As for the active/passive switch, what is the difference between the 2 diagrams? is either of them better?

 

[4StringTheorist]

Thanks 4stringtheorist & ABtheBassPlayer!

would an on-on-on work like in this diagram? Ignoring the "bass-cut"/"treble-cut" wording

Yes. That'd make a DPDT on-on-on work. Combine cap values to taste.

 

[4StringTheorist]

Thanks guys, I have one last question.

As for the active/passive switch, what is the difference between the 2 diagrams? is either of them better?

Not as far as I can tell. For my own bass, I used the circuit shown with the green box. "True bypass" your diagram calls it (though I don't see it as any more true a bypass than the other diagram.. I just like how clean the wire routing is. )

 

[basillio]

I have been scouring the internet for a diagram that shows how to wire the passive tone before the preamp but have not had any luck. The only thing I found was this from a seymour duncan article but it doesn't make any sense to me. I'm a little lost when it comes how to wire the volume -> tone -> Preamp and have a few questions.

1. Is the SD wiring diagram stay the same and simply add the passive/active switch to the Ground and hot input where the output jack is indicated?
2. Do I have to wire the Volume-to-Tone pots differently so that the hot output is different (coming from the tone pot)? *don't know if this is even possible*

 

[ABtheBassPlayer]

My suggestion would be use the P-Bass wiring like the one you posted, but connect the output wire from the volume to the active/passive switch. I would also go for the second diagram on your first post. I’ve added your pictures just to be clear.

I would then connect the middle lug of the tone pot to the cap selector switch.

 

[basillio]

Awesome guys, thanks a million. I'm gonna be trying out the wiring when I get the new switches.

 

[JohnJenkins]

How did it work out?