Quick Question for the Hi-Fi Gurus

[Ribbit]

I've just been given a couple of old hi-fi speakers. They just have bare (i.e. no connectors) speaker wire coming out of them. One wire on each is brown, one is blue.

- So, which wire is which?

- I want to put phono plugs (I think they're called RCA plugs in the US) on them for my amplifier. Which wire should go to the pin, and which to the sheath?

[VJ]

Well, on an old in-car amplifier (Philips, was standard mount in a Renault GTX), the coding for the speaker wires was:
Blue wires are + positive
Brown wires are - negative
(I don't know if this your wires are similar... )

As for the RCA:

http://home.att.net/~chimeraone/audiolitzwirebraid.html

The best RCA plugs are the ones constructed like the Vampire 800 series or the Cardas types.
These plugs have an outer body with a milled slot to provide access to the center positive pin. Since the interconnect Litz braid has 4 strands, the two positive are soldered to the center pin and the two negative strands are soldered to the right and left side face of the slot. You solder the negative strands right at the front edge of the slot, positioning all strands(positive and negative) to ensure they will have the same wire length to the outlet of the connector.

http://www.ecmtb.com/howto/lights.shtml

Using the soldering iron, solder the positive wire pigtail to the inner terminal. Then solder the negative wire pigtail to the outer RCA terminal.

On a side note:
Do not mistake positive and negative signal with positive and negative audio as present in balanced systems; some systems use 2 wire RCA for a balanced audio signal:

http://www.audiocontrol.com/MobileAudio/Support/FAQs/

Jörg

[Jon P. Inghram]

Or just tap a 9v battery against it and see which direction it moves. I wouldn't suggest you HOLD the battery against it though, unless you like burning and/or melting things.