The Magazine's Personal Tech column Sunday gave incorrect advice on cleaning records. The cleaning solution should be a mixture of 4 parts distilled water and 1 part pure isopropyl alcohol, used only with a record vacuum. (Published 11/18/87)

The last thing you need to hear on a weekend is another "should" message. You get them all week long: at home, at work, at school. You should floss your teeth. You should change your oil. You should eat a low-fat diet.

But let's face it. You can't get away from should messages. And I'm about to give you another.

You should take good care of your audio equipment.

Exciting, huh? Okay, equipment maintenance isn't a glitzy subject, but it's more pleasurable than paying repair bills on your cassette deck or CD player. A few minutes of mindless labor every now and then can keep the music clear and bright. So you should pay attention.

CLEANING COMPACT DISCS: A lot of people still believe that CDs are virtually indestructible, immune to dust and fingerprints. They aren't. CDs don't demand the meticulous cleaning required by LPs, but they still need gentle care to keep them pristine. Think of a CD's polycarbonate plastic surface as a window through which the laser reads data. The window must be clean, but constantly polishing the disc will eventually scratch it. The lesson here: Keep your CDs clean enough so you don't need to wipe them down before each playing.

All it takes to clean a disc is a soft, lint-free cloth and a light spray of Windex. Gently wipe the disc from the center hole out -- not in the circular pattern you'd use on an LP.

CDs have spiral grooves that the laser scans, reading the digital data embedded in microscopic pits. By wiping CDs from the center out, you'll avoid making scratches along a consecutive line of these pits. If CDs must be scratched, better the abrasions be light and inaudible.

You can restore the surface of a mildly scratched CD with a trick I learned from David Maggin, Myer-Emco's manager of high-end equipment. After experimenting with three brands of toothpaste, Maggin found that polishing a disc with a soft cloth and a light coating of Crest Tartar Control toothpaste protected it against skips and laser mistracking.

CLEANING RECORDS: While audiophiles are still arguing over which sound better, CDs or LPs, the indisputable fact is that vinyl demands fussy cleaning. Lasers read through minor imperfections, but a stylus tracking an LP's grooves translates every mote into clicks, pops and annoying crackles. Begin with a dry carbon-fiber brush, which acts as a magnet for dust particles, cleaning your LPs before each play.

There are also various cleaning solutions available for records, but many of these leave residues that in time can make more noise than they cure. If you must use a liquid to remove heavy concentrations of dust, try mixing 4 parts of pure isopropyl alcohol (not rubbing alcohol) with 1 part distilled water. Apply sparingly with a record brush and let records dry before playing.

Keeping records dust-free in winter is harder because dry air promotes static electricity. After cleaning the record, you might want to use an anti-static gizmo such as the $15 Nagaoka Kilovolt. This device sprays a stream of negative ions onto the record's surface, neutralizing the positively charged dust particles.

For spotless albums you'll need a record vacuum cleaner, not cheap (they start at about $240) but the only effective way to remove ground-in dust and the residue left from the manufacturing process.

CLEANING CASSETTE DECKS: One of the worst enemies prerecorded cassettes have -- aside from dirt, excessive heat and small children -- is magnetism, which can erase or damage them. Yet because cassette players are surrounded by electrical energy, certain of their parts contacting the tape become slightly magnetized during normal operation. Merely playing your tapes in a strongly magnetized machine can harm them. Because such damage is irreversible, your best defense is prevention.

Demagnetize your deck every few months, more often if you use the machine several hours a day. You can use a cassette-size demagnetizer that pops into the deck like a tape (especially good for car decks) or a probe type that plugs into an AC outlet. The latter is really a powerful hand-held electromagnet, so keep all your tapes several feet away when you're using it.

You'll also need to remove dirt and oxides from the heads, pinch rollers, capstans and tape guides after about every 10 hours of playing. There are several cassette-size cleaning tapes on the market, but none is as effective as doing it by hand, gently scrubbing the parts with cotton swabs dampened with pure isopropyl or denatured alcohol.

None of these simple procedures takes more than 10 minutes; all will protect your audio equipment and increase your enjoyment of music. ::