Power supply cable

[jrmintz]

Hi all,

Is a piece of 4 conductor stranded signal cable, similar to Canare Star Quad suitable for use between an outboard +24v/phantom supply and 2 Neve mic pres? I think it's 20 or 22 guage. Is there a better choice?

Thanks,

 

[NewYorkDave]

It would be OK for +/-24V at low to medium current, since you could double up the conductors, and it's low voltage. But +/-24V PLUS phantom? No, I wouldn't.

Belden 9418 seems suitable.

 

[kiira]

[quote author="jrmintz"]Hi all,

Is a piece of 4 conductor stranded signal cable, similar to Canare Star Quad suitable for use between an outboard +24v/phantom supply and 2 Neve mic pres? I think it's 20 or 22 guage. Is there a better choice?
[/quote]

hi hi

Yes real Canare star Quad is perfect for this because it is rated to 500V. I have used it for B+ tube amp voltages.

 

[NewYorkDave]

Kiira,

Don't forget, a typical tube preamp, line amp or whatever draws plate current down in the milliamp range, where conductor resistance isn't a real problem. (Heater current's another matter entirely). Solid state gear, although operating at lower voltages, often draws higher current--especially discrete gear designed to pump +24dBM or more into 600 ohms.

 

[kiira]

[quote author="NewYorkDave"]Kiira,

Don't forget, a typical tube preamp, line amp or whatever draws plate current down in the milliamp range, where conductor resistance isn't a real problem. (Heater current's another matter entirely). Solid state gear, although operating at lower voltages, often draws higher current--especially discrete gear designed to pump +24dBM or more into 600 ohms.[/quote]

haha oopsie. Never Mind. Thank you for the info... I figured if it could handle 400V. to my preamp it could do 48.

note to self: learn Ohm's Law and that other math stuff!

 

[jrmintz]

Thanks Dave, Kiira.

The preamp is just +24 and +48 and it draws about 220 mA with no signal going in. I'll get some Belden.

:thumb: :guinness:

 

[soundguy]

In the case of +24v and +48v, is there any drawback to using the shield for a common 0v from the two supplies? Ive done this in a pinch but it never seemed like the right thing to do. Used a pair for 24, pair for 48 and 0v on the shield. I guess the question is, assuming the wire in the pairs is appropriate for the application's current draw, is there a technical reason not to use the shiled for 0v and lean towards an insulated wire instead?

dave

 

[jrmintz]

In the case of +24v and +48v, is there any drawback to using the shield for a common 0v from the two supplies?

I hadn't thought of that, but I could do that if there's no reason not to. Could the drain wire be used for 0V if I double up the conductors?

:guinness:

 

[NewYorkDave]

Yes, that should work.

If your preamps are drawing 200mA-plus and the wire is 20 or 22ga., you definitely need to double it up.

As you can tell, I mis-read your original question. I was thinking that you wanted to put three supplies plus ground over that wire, not just two.

 

[jrmintz]

[quote author="NewYorkDave"]
As you can tell, I mis-read your original question. I was thinking that you wanted to put three supplies plus ground over that wire, not just two.[/quote]

Thanks Dave,

That's OK, I also didn't actually look at the wire carefully enough - it's actually 24 guage. So I think I'll go with something heavier all around.

Thanks again for your help.

:thumb: :thumb:

 

[BradAvenson]

You might think about using speaker cables, like those twistlock speakon connectors. I know there is some 2 and 4 conductor stuff around.