STK-S4 split wiring

[mcentee2]

Hi

Just bought a set of classic stacks and was looking at the option to wire them via single push-pull to split them all at once .....just so I can hear the difference between noise cancelling mode and vs my ssl1's.

Anyway, the SD diagrams I have found are fine except I really do not understand why the middle pickup's RED wire goes direct to one half of a DPDT whilst the neck and bridge reds go to the 5 way switch.

Why doesn't the middle RED go to the 5 way to its relevant tag and then the common go to an spst to ground?

....does not compute....

 

[Chistopher]

Re: STK-S4 split wiring

The middle wire is the split wire. When it is connected to ground the pickup is split.

 

[mcentee2]

Re: STK-S4 split wiring

Not sure I was clear enough, I mean all 3 pickups are stacks, the diagram shows the middle pickup's red wire going to a dpdt switch, whilst the neck and bridge red wires go to one side of a standard 5 way with common to ground.

I know that the red wire from each stack is the split wire to ground.

 

[Chistopher]

Re: STK-S4 split wiring

What's the issue then? The switch determines whether the red wire goes go ground or not. When the switch is on, the red wire goes to ground, splitting the coil, when the switch is off the red wire goes no where and the coil remains noiseless.

Are you trying to say there is something wrong with the diagram? If so, show us.

 

[mcentee2]

Re: STK-S4 split wiring

Apologies, this is the SD wiring diagram:

https://www.seymourduncan.com/wp-content/uploads/2015/05/3STKplus_5W_1Vpp3SPL_1T.jpg

I am trying to understand the use of the dpdt in terms of the middle stack pickup's red wire which goes direct to one side of the dpdt, in contrast to both red wires from neck and bridge stacks that go to one side of the 5 way and then to the other side of the dpdt.

I would like to know the reason why the middle pickup's red wire does not also go to the spare tab on the 5 way, then I only need an SPST or SPDT for the path to ground.

 

[mcentee2]

Re: STK-S4 split wiring

If it helps anyone in future, I just wired the stacks in and put all 3 red split wires into the 5 way, and it works perfectly.

Didn't need a DPDT, used an spdt, but an spst would have done.

I still don't understand why SD diagram uses a dpdt both sides for this.

 

[gregory]

Re: STK-S4 split wiring

The 5-way and dpdt switches allow the bottom hum-cancelling coils of all three pickups to be independent of one another in noiseless mode.

If you put all three red wires to the switch then in the notch positions in noiseless mode you're putting the bottom coils in parallel, the top coils in parallel and connecting the two pairs of parallel coils in series.

You might think it works perfectly, but it doesn't. If you're mixing different models like combining an S4B, S7 or S6 in the bridge with an S4M in the middle, just as an example, the problem may be more noticeable. The individually tuned pickups were not intended to operate that way.

 

[mcentee2]

Re: STK-S4 split wiring

@gregory

Many many thanks, that is a majestic answer!

...Back to the soldering iron