STC-3M4 Slap switch does not work

[bassliner]

Hi.
I have registered just a while ago, and this is my first posting.

I have got a used Seymour Duncan STC-3M4 bass preamp. The three tone pots and the volume pot work fine and sound great, but the slap switch has a very low effect, if any. I have tried all the positions of the two preset potentiometers on board. Measured the switch with an ohm meter, and the contacts seem to work well while activated.

I took a close look at the wirings. Compared to the original wiring diagram (link attached), the two wires from the slap switch, brown and green/white striped, seem to be swapped at the connector end (circuit board end). So that the brown wire is at the connector’s right end, and the green white striped is second from right. At the slap switch end those wires are as pictured, as well as the green and purple wires from slap switch to the pots.

Anyone who has experience of the STC preamp electronics, do You think this could cause the problem?

https://www.seymourduncan.com/wiring-diagrams?meta_params=bass-options,1-pickup,bridge-mm

 

[bassliner]

Re: STC-3M4 Slap switch does not work

Got a reply from Dennis at Seymour Duncan tech support, to flip those two wires. I did it and now the switch has a strong effect. Maybe the wires were originally installed the wrong way, or someone has modified them later, but who cares, now it works.

 

[jeremy]

Re: STC-3M4 Slap switch does not work

glad it was a simple fix and its working properly now!