Wiring help

[rhysjackson]

Hi guys,

I'm putting together a custom Warmoth bass and would like to attempt the wiring myself. However, I'm new to this and could do with some expert guidance to help me learn. All feedback welcome.

After a lot of reading I've attempted a wiring diagram, but feel out of my depth and likely made a mess along the way. Could anyone show me the errors, and point me in the right direction to fixing them?

The setup I hope to achieve is:

• 3 position switch for MM bridge pickup (parallel/single-coil/series)
• 3 position pickup selector switch (Neck/Both/Bridge) (no blend pot)
• Volume pot with push/pull (active/passive)
• Darkglass tone capsule pre-amp (with pots for bass/low-mid/high-mid)

In particular, I don't feel like I understand how the earth/ground should be wired.

Here's an idea of what the controls might look like on the bass:

And here's my attempt at planning the wiring:

Thanks in advance!

 

[Killed_by_Death]

I don't feel like I understand how the earth/ground should be wired.

For the signal to be picked up by the amp it requires two connectors, (-)ground & (+)signal.
In a bass, chassis ground is any spot that needs to be electrically connected to the sleeve side of the output jack, labeled S in your drawing.
You can check that all ground points have continuity with that point with a multimeter set to the lowest Ohms reading, Ω

 

[rhysjackson]

ground is any spot that needs to be electrically connected to the sleeve side of the output jack

This makes sense, thanks for clearing that up. I'm struggling to identify which spots need to be connected to the sleeve side. Does every component in the circuit need to have a ground connection? Something doesn't feel right to me about having no ground on two of the switches.

You can check that all ground points have continuity with that point with a multimeter set to the lowest Ohms reading, Ω

This will be invaluable, thank you.

Thanks again for helping me out here, I realise this is probably electronics 101! I'd be happy to try and figure out more by myself if you have any great learning resources.

 

[Killed_by_Death]

If the bass has shielding paint or copper foil in the cavity, those switches will automatically be grounded through their connection to the shielding, same goes for the output jack.

here's a lot of learning:

Neets - Naval Electrical Engineering Training Series

 

[rhysjackson]

Fantastic, thank you. I think you've just sorted me out with enough reading for the next year!

 

[RobbieK]

And here's my attempt at planning the wiring:

It looks ok, except that the volume pot is not wired correctly. The signal from the pickup should go to the clockwise lug, and the signal to the preamp should come from the wiper. You also haven't included an earth wire from the bridge.

As for earth connections. Well you have to understand which things need earthing for the circuit to work properly, and which need earthing simply for the purposes of shielding. The former have to be soldered to earth, but with the latter, a mechanical connection to your shielding tape or metal plate is fine, and sometimes preferable (pot casings, switch bodies).

The things that need a soldered wire to earth are: earth side of the pickup coils, earth wires from that lug of the series/single/para switch, earth wire from the preamp, the anti-clockwise lug of the volume pot, sleeve lug of the jack. These all need to be connected together with soldered connections.

Stuff like the pot casings, switch bodies, can be soldered to, but with shielding tape and/or a metal plate, it is not necessary, and in the case of a mini toggle will probably ruin the switch. The braided shielding from the humbucker lead doesn't actually need to be earthed for the circuit to work. But of course, it's a very good idea to connect this to earth, and soldering is of course the way to do that.

 

[rhysjackson]

It looks ok, except that the volume pot is not wired correctly.

Got it now, thanks for pointing that out.

Thank you for all the earthing information, that's helped my understanding a lot.

I feel confident about giving this a shot now and will post the results in a couple of months when it all comes together!

 

[Killed_by_Death]

9 months, that's how long it should take you to get through the NEETS, or at least that's how long they give the students during training.