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Wiring a Bartolini NTMB active/passive switch?

Discussion in 'Pickups & Electronics [BG]' started by fourstringbliss, Feb 17, 2014.

  1. I'm going to be installing a Bart NTMB in my bass, but this one doesn't seem to come with instructions on how to wire in an active/passive switch.

    Here's the wiring diagram:


    How would I wire in an active passive switch?
  2. ex-tension


    Jun 11, 2009
  3. The problem is that you have a 25k volume pot. If you do active/passive switching, this will either have to be changed to 250k/500k, for passive pickups, and moved before the preamp input, or, you will have to live without a volume control in passive mode.
  4. I'm actually totally okay without a volume control in passive mode. I never mess with the volume anyway, always leaving it dimed. I started a thread before this one asking about leaving out the volume control because of a limited number of holes. It was suggested that I should connect the green output wire to the tip lug on the output jack and then connect that to a 25k resistor connected to the jack ground tab. Should I do this? Do I need to?
  5. That's going to kill the output in passive mode. The resistor should be switched by the active/passive switch so that it is only in the circuit when the preamp is.
  6. DWBass

    DWBass The Funkfather

    Can't you just route another hole?
  7. Here's the wiring diagram for the active/passive switch:


    What would you connect the resistor to?
  8. Here's the bass in question, just minus the wood thumbrest and put another toggle switch between the two lowest knobs.


    I don't want to put another knob on there - there are enough as is! Right now I'm debating whether to keep those two toggle switches as series/single/parallel switches for the pickups and drill a couple of holes for the midrange freq. switch and active/passive, or if I should hardwire the pups in series and put those other switches in those holes - so I don't end up with that guy with all the switches!
  9. I wouldn't use that diagram, as it leaves the preamp input open in passive mode. It is best to ground the preamp input, to prevent switch pop.

    Here is a better diagram:

    Place the resistor between the preamp's output and ground.
  10. line6man to the rescue!

    Let me see if I understand this completely. I'm going to connect the output from my blend control to the switch lug you have labeled, "output from volume controls". I'm going to connect the yellow preamp wire to the switch lug you have labeled, "preamp input". I'm going to connect the green preamp wire (that would go to the volume control) to the switch lug you have labeled, "preamp output". Then there's a wire that goes from the switch to ground and from the switch to the output jack. Is this all correct?

    Where do I connect that resistor in all of that?
  11. Does he mean to wire in the resistor between the "ground" lug and "preamp output" lug on the switch?
  12. Yes.