Dedicated lines

Thanks guys for your input. Is there a prefered splicing guide somewhere that I might consult or is it just a twist and shield situation?
08-10-09: Markus1299

Markus are you going to do this job yourself or are you having an electrician do the job? I assume from looking at your system you will hire an electrician.

The electrician you hire will have his preferences how he likes to make a splice.

I would recommend he first twist the (2) #10 solid conductors together clockwise.
Then cut off the end of the twisted pair even, leaving about 1" of bare copper showing.
Next install a grey Scotchlok Electrical Spring Connector over each twisted pair of #10 wires.

If you want an air tight connection solder the wires after they have been twisted together and then install the grey Scotchlok over the wires.

The Scotchlok should be turned on clockwise as tight as possible..... tight..... for the spring connector to work properly.

What was installed, based on my reviewing the runs, was inside metal conduit (which i believe is code in my area considering how it was run - semi exposed in a "crawl space" ceiling. There were 3 wires + - ground.
08-18-09: Ckoffend

There were 3 wires + - ground.

Four individual insulated conductors? More than likely THHN/THWN insulation......
Like 2 hots, 1 white neutral, and 1 green ground conductor?
If yes, you have a 3 wire multi conductor branch circuit. Two separate circuits with a shared neutral. Not 2 dedicated circuits.
Not particularly good for audio equipment connected together by ics.
.