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Series paralell switch and selcectable coil split?

Will_White

Will_White

Jul 1, 2011
4,176
5,808
Salem, OR
#1
So I've been thinking about changing up the wiring on a bass with an SD nyc 5 bass pickup, it's a four conductor humbucker and I was wanting to know if it would work to have a series parallel switch, and a coil split that would be selectable front and back coils, its ok if one switch is reliant on the position of the other to work properly. I know that these work in isolation but would this work together? I also want to have a toggle that switches between capacitors on the tone knob and can be switched so it would act as a bass cut as well, eg high value, then standard value, then bass cut, will these all work together? It will have a stacked volume and tone and then three switches.
 
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#2
3396717987_d7d0eee10e_o.png
 
#3
thank you for the diagram. Can you explain how it works for me please? Does the series parralel/switch have to be in the series position? What happens if it's in parallel and the split switch gets bumped to one of the split positions
 
#8
Will_White said:
That's actually great, I was planning on adding a kill switch anyway. Any thoughts on switching between two cap values and a bass cut?
Click to expand...

That won't work. You would need a triple ganged concentric pot, which are difficult to find. If you want to skip the concentric volume/tone and have separate pots, then you can do it with a dual ganged pot. 250k or 500k for the treble cut, and 1M for the bass cut. A more practical solution would be volume and bass/treble cut on a concentric pot. Or, skip the pot and have a fixed switch.
 
#10
Will_White said:
Why can't I just do it with a single 500k pot? The site I found the bass cut circuit on shows it with a 500k pot. If I do it with a switch I can still use the treble cut with it to give "more" mids right,
Click to expand...

Bass cuts work by running a capacitor in series with the signal path. You place a pot parallel to the capacitor to bleed the signal across the capacitor, varying the amount of cut. If you choose too low of a resistance range, the performance of the pot is compromised. You can't cut as much bass as you move through the rotation, because the resistance stays low throughout most of the taper. Additionally, you need more complex switching to get the job done. Having two pots ganged together lets you use a simple DPDT center-off switch.
 
#14
Will_White said:
So it needs 3 poles because it has to be taken completely out of the circuit and it needs a different common? Why can't I just have it always connected to one end and have the switch complete the circuit, making it a 2p3t switch
Click to expand...

One pole switches the input, one pole switches the output, and one pole switches the pot. Remember that the pot is having to be rewired from series to parallel, so you need additional poles. With only three poles, the pot has to be backwards for one mode, since high resistance is flat for a treble cut, but a bypass for a bass cut. That's why the fourth pole is desirable for practicality. Either way, two poles won't be enough.

This is the simplified 3P3T version.
16217875779_6142bd53ef_o.png
 
#16
line6man said:
One pole switches the input, one pole switches the output, and one pole switches the pot. Remember that the pot is having to be rewired from series to parallel, so you need additional poles. With only three poles, the pot has to be backwards for one mode, since high resistance is flat for a treble cut, but a bypass for a bass cut. That's why the fourth pole is desirable for practicality. Either way, two poles won't be enough.

This is the simplified 3P3T version.
16217875779_6142bd53ef_o.png
Click to expand...
Would this switch work?
http://www.allparts.com/EP-4363-010-4-Pole-On-On-On-4PDT-Mini-Switch_p_1404.html
 
#18
line6man said:
No. That is a 4PDT. You need a 3P3T or 4P3T. A 3P3T will have 12 terminals, and a 4P3T will have 16 terminals.
Click to expand...
So I can't seem to find a 3t3p or 3t4p switch that isn't out of my budget, so what would you suggest for a fixed or two value bass cut switch, and if I used both the bass cut and treble cut at the same time it would result in "more" mids right, and I would only need a dpdt center on switch for switching the cap values, for a high, low, and no cap. Could I make it completely eliminate the pot from the circuit in one of the positions?
 
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#20
What I would do is skip all of this complicated stuff and do the following:
One DPDT On/On/On switch to select between two capacitors and a bypass for bass cut.
One DPDT On/On/On swtch to select between three capacitors for a tone control.
-Or-
One DPDT center-off switch to select between a bass cut, treble cut (with or without a tone control), and bypass. No other switches or pots.
 

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