New construction and speaker wire

[rick]

Can I run regular speaker wire thru existing holes used for other wire such as electrical wire, cat5e wire or intercom wire?

[suemarkp]

Per NEC rules, low voltage cable and NM cables may touch each other (or use the same hole). At termination points, the high voltage and low voltage must be in different boxes or separated by a barrier (this shouldn't be relevant for your question). However, to use your speaker cable in the wall it must be listed cable. Typically, it will be labeled "CL2" for this purpose. Regular speaker cable, monster speaker cable, and most others are not listed. Radio Shack has zip cord (looks like lamp cord) that is listed CL2 in sizes up to 14 gauge. That is what I'd run in the walls for speakers. You may also give your electrical inspector a shock when he sees that running with your NM cable -- he'll be wonder what circuit that powers which would be a major violation if used for 120V branch circuits.

I would keep low level signals (network, phone, intercom, CATV) separated from higher power cables (speakers and regular house circuits) by at least 2" and preferably 12". It is OK if these two classes of cabling touch each other where they cross at 90 degree angles. A purist may want three levels of cable separation -- regular power, speaker, and other low voltage. It just depends on how many sets of holes you want to drill or have room to drill.