If past events are any guide, a unique sort of record player announced by Phillips may prove to be the prototype for the kind of equipment many of us will be using at home by the mid-1980s. the new development in discs bears a striking parallel to the original casette format in tape -- novel, but also compatible with existing equipment and stereo system "philosophy."

The item in question is the so-called cd (for compact disc) system. It involves both a new kind of disc recording and a new kind of player. However, the whole thing is conceived and suggested not as a replacement for existing systems, but as an optional adjunct, an "attachment" that may be added.

The record itself is digitally encoded. Instead of a groove cut with wiggles that represent the sound, the new disc contains a series of microscopic pits and flat sections. The record is only 4 1/2 inches in diameter and thin as a dime. The signal is sensed by a laser-beam system installed under the turntable. The disc is placed trackside down on the machine, and is played from the inside out. Only one side of the disc is encoded with audio material, but it can hold a full hour of program, a bit more than both sides of a conventional 12-inch disc.

Built into the machine is a digital-to-analog decoder, which changes the encoded signal into electrical impulses. These are the same as the signal now available from conventional phono pickups, so they may be connected directly into the standard phono jack inputs found on normal amplifiers and receivers.

With its small disc and associated electronics, the entire Phillips player is about as big as a medium-size cassette deck, certainly smaller than many of today's top-quality turntables. Yet, performance is said to be audibly superior. Among the claims made for the new system are: no rumble, wow or flutter; enhanced dynamic range up to 85 db (which beats present-day master tapes); and no record wear, since there is no physical contact between the record and the system tracking it.

As certain as Phillips is about all this, they are equally uncertain as to just when the new systm will hit the market, or what it will cost. The only answers to these questions now are, respectively, "in a few years" and "about the price of a good conventional turntable." Also to be considered as a strong possibility -- in view of what happened with cassettes, which also originated with Philips -- is the licensing of other manufacturers and of record companies to make the equipment and the discs. FEEDBACK

Q: I can understand how too much amplifier power can damage a speaker. But someone told me that when a speaker needing high power is hooked up to an amp or receiver that is low-powered damage also can result How come?

A: The danger of damage in the latter kind of hookup lies in the possibility of the low-powered amp or receiver "straining" its circuits to supply the power "demanded" of it by the speaker. If no safety cutoff is built into the set, it could blow its output transistors. A possible side-effect then could also be a burned-out voice-coil in the speaker system.