Q I have a mid-1980s NAD 7140 receiver that sounds great. Lately when I adjust the volume or balance knob there is static in the left speaker. A few seconds of jiggling removes the static and gets it back on track. My guess is the pots need replacing. I'd prefer to have it fixed, rather than buy a home theater receiver for $500, but I don't know if it's wise to put $200 or more into repairs for a receiver that old. Do you have any thoughts on my dilemma?

A Static when you turn the knobs is often fixed with a simple cleaning, which removes dust that has found its way into the contacts. You can try taking off the top cover (with the receiver having been unplugged for several hours, of course) and spraying contact cleaner into the spots behind the knobs and turning them back and forth to work in the cleaner. If you really want to be sure, take it to a repair shop. They will likely recognize the problem and recommend a check-up and cleaning. A reputable shop will charge well under $200 for this service.

In any event, I recommend keeping the NAD rather than replacing it with a home theater receiver, even if it costs $200. The 1980s was something of a golden age for audio and not many modern pieces can match the NAD for two-channel sound quality. I have two NAD pieces from that generation, an amplifier and a receiver. They have each needed one repair costing under $150 and are still working fine today. In fact, one is in pretty much constant use driving very large, inefficient speakers in my main theater room.

Anyone looking to build a two-channel system should strongly consider 1980s-vintage gear for receivers and amplification. You will get better performance in almost all cases and it may cost less as well. Lots of it is available on sites like eBay and Craigslist. Some brands to look for are Adcom, B&K, Harman/Kardon, NAD, Parasound and Rotel. I once picked up an 80-watt Rotel receiver on Craigslist for only $50, one of the best deals I have ever found on audio gear.

Glasses-free 3-D updateSome time ago I answered a reader question regarding glasses-free 3-D HDTVs and a Toshiba model that was recently introduced in Japan. I said I could not comment on the picture quality because I had not seen it. Well, I finally saw an example of the picture quality at the 2011 Consumer Electronics Show and frankly, I think it was awful. The screen looks like it has lines in it if you turn your head, and at times looks quite fuzzy. The 3-D effect itself is not all that strong and is far inferior to systems using active shutter glasses. I'd rather have good, clean-looking 2-D HDTV than awful-looking 3-D HDTV.

If you want 3-D you need to accept that glasses are necessary to create the best experience. If what I saw at CES is any hint of things to come, it will likely always be this way.

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