In case you haven't noticed, the speakers being offered for stereo systems in cars (and vans, etc.) have been getting better. Maybe this says something about the psycho-socio-cultural role of the automobile, but it also has an interesting spinoff for stereo in general.

It isn't a very big engineering step from a speaker primarily intended for car installation to a boxed version going under such names as "mini-speaker" or "micro-speaker." In the last few months, a surprising (and apparently increasing) number of firms have been offering such models. One might well ask what kind of sound can be expected from these petite units? The answer is, with the exception of he deep bass, these speakers can sound quite good. They can provide listenable (though not the most spectacular) stereo in small- to medium-size rooms using systems built around a low- to medium-powered receiver or amplifier.

For those who want more bass, some mini-speaker companies are offering a third unit, which is purely a bass speaker, sometimes known as a subwoofer or a "bass extender." In such a three-piece speaker system, the deepest bass from both stereo channels is handled by the larger bass unit, while middles and highs are handled by the pair or smaller units, which then are called "satellites."

The new "speaker-trio" approach may relate to another recently noted trend - that of a product glut developing in high-end auto stereo equipemnt. That would make the speaker-trio idea a clever marketing ploy, of course, bu that in itself should not rule out the possibility for some very good stereo sound in an unusual, and uniquely appealing, format.

Q: I am thrilled with the sound of a 200-watt per channel amplifier, but I am also miffed by the information that this monster might use over 1,000 watts of increasingly expensive electrical energy from my AC power line. Should I forget it and buy a lower powered amplifier?

A: Not necessarily. The 1,000-watt drain on the power line would occur only (if at all) on sudden mighty musical peaks that might drive the amplifier to its maximum output level. These instances occur rarely and they last less than a second. Most of the time, even if you play your music fairly loudly, they amplifier will draw less than 200 watts fromt he power line.