Adding DC jacks to positive ground circuits?

[carboncomp]

If I'm going to add a DC jacks to positive ground circuit, do I just need to make sure the dc jack is wired with battery + going to ring, and battery - going to center? 

Or is there some elaborate power filtering circuit needed too?

[skrunk]

http://www.generalguitargadgets.com/diagrams/switch_lo_3pdt_tb_dcj_pnp_gi.gif

[R.G.]

The practical thing to do for a DC jack is to put in a jack and make its wiring match the industry standard that Boss set with its power supplies. That is,
center pin = negative, barrel positive.

The problem then is how do you make this match the negative ground requirement? The obvious way is to use a single-chip charge pump converter to make -9V out of +9V, and put this between the power jack and the effect circuit. This ensures that both your power supply and your effect circuit can share the common grounding of any other effects and not have power problems.

Note that rewiring your effect to reverse the power and ground to fake a negative ground may well give you problems with oscillation and noise.

[carboncomp]

So for the best result, I want to go Boss PSU>DC jack>charge pump>effect

And then wire all the grounding for the jacks LED and so on from the output rails of the change pump?

[R.G.]

So for the best result, I want to go Boss PSU>DC jack>charge pump>effect

And then wire all the grounding for the jacks LED and so on from the output rails of the change pump?

As you know if you read my periodic rants, "best" is hard to quantify. I personally think this is the most trouble-free way to do it.

Notice that the incoming negative terminal on the DC jack will be ground for the entire circuit, including the effect circuit. The inverting charge pump has only one duty, that being to make -9V out of +9V, and send it on to the effect circuit for power. If you use a 3PDT switch to get an LED, then you can power the resistor/LED from the existing +9V, as this has nothing to do with the circuit at all. It only tells you what position the switch is in.