running wire in walls/floor

ABS can work. also, there is a flexible conduit that is a blue/green color that is often added to new construction and add-ons. this way someone can pull whatever he wants as times change. someday we will be pulling fibre optics for phone service through our houses.

Jdodmead, there are plendy of decent installers who can do what you want. Check out custom telephone/cable T.V. installers in your area.

We are currectly remodeling a house, and I have done what Pbb mentioned. My first thought was to use PVC pipe, but my electrician informed me of a product mfg'd by Carlon - it's a blue flexible corrugated plastic pipe in sizes from 1/2" up to 1 1/4 inch. Locally they call it "Smurf" because of it's color. Lowe's sells it in 10 ft. joints, or you can buy off the spool at your local Electrical supply house. The family room is new construction, so it was relatively easy to install by running under the floor in the crawl space. I had 3 runs for the rear spkrs and sub. The ends terminate at the opening of a "frame", which is plastic and provides a border for the drywall to be cut around. They use these now for running phone and multimedia wiring. I intend to cover the frames with switch plates, which will provide the opening for the cable to pass through. Makes for a very neat installation. Existing construction may pose a few more problems - you will have to have access from either a crawl, basement or attic, and if you're dealing w/ exterior walls, the insulation may make it difficult to feed in the tubing. Would make a good weekend project for the DIY'er, or check with your electrician.

smurf tube's tough to get many speaker cables through because it is corrugated, fairly small and flexible whereas PVC or ABS is smoother, but takes longer to install (and can be more difficult because of its larger diameter needed to accomodate your fat cables)

Pbb, installers and people do what you suggest and have done it for a while, it's a smart idea and works well, provided you allow for the actual pulling of the cables and the fact that many hi-end cables are jacketed with materials that are not slippery or durable enough to put up with more than about 2 bends without causing major problems and occasional damage due to friction in the conduit (and who wants to smear their expensive cables with the fancy jacket with conduit lube- kinda kills the resale...)

Cables (speaker or interconnect) with networks also pose a problem. At least one cable manufacturer offers speaker cables in different performance levels with a Neutrik wall plate that attaches a pigtail with the network on it. They don't comment on the effects of adding those connections to their cables, and claim the network takes care of any problems as a result.

Lastly, don't tie the end of the new cable to the end of the old and pull away. Pull a piece of nylon cord through the conduit with your old cable on its way out, then use the strong, thin cord to pull your new speaker cable. It's half the friction that way.