TV SOUND CATCHING UP WITH VISUALS

So you’re fed up with your tiny, tinny TV speaker. You long for the day when you can hear the Stupid Pet Tricks on the Letterman Show in full, glorious stereo.

Haven’t you heard? TV sound has finally caught up with the vision part of television--even surpassed it. Couch potatoes in Europe and Japan may get a sharper picture than we do, and the wonder of HDTV (high-definition television) is still a few years away, but in terms of sound the future is here.

If you’ve got the cold, hard cash.

Just as movie theaters had to do some expensive reequipping when sound came to film, the changes in TV/VCR sound mean that broadcasters, manufacturers and consumers will have to make some costly alterations--if they haven’t already. Broadcast and cable networks are increasingly adapting multichannel TV sound (MTS), and most new movie and music videocassettes come in stereo hi-fi.

Need a little help riding the new wave in video sound? We can’t cover all the details in this space, but here are some essentials.

Stereo and Hi-Fi. First thing: don’t confuse the two. There are machines that provide stereo without hi-fi--especially older models. So make sure you’re getting both features.

If you buy a hi-fi/stereo VCR and connect it to a stereo system with good speakers, you can have dramatically improved sound, no matter what kind of TV you have. A large portion of the prerecorded tapes you can rent are in hi-fi/stereo. In addition, hi-fi machines will give you better sound on your own recordings (by recording across almost the entire width of half-inch blank tapes). The improvement, though, won’t be that dramatic unless you have a tape deck or TV capable of receiving MTS (see below)--or unless you plug into a simulcast on your stereo system, or add your own audio track.

Hi-fi was introduced in some Beta decks two years ago, but started showing up in a large number of VHS decks only this year. Now almost every manufacturer makes at least one hi-fi/stereo model. It’s a feature that’s going to add $100 or more to the cost of your purchase.

If you do make that big hi-fi buy, though, there’s a bonus: Videotape for both Beta and VHS reproduces a high-fidelity sound superior to regular audio tape--in fact, surpassed only by compact discs on the home front. (There’s considerable debate over the quality of sound in the new 8-millimeter format, so remarks here do not apply to it).

Since videotape is also capable of recording far longer on one reel than audio tape, you may also want to use your VCR for audio-only use as well. (Make sure your model has an audio-only switch, since it may provide an even better signal-to-noise ratio for this purpose).

Some decks also come with Dolby noise reduction, which reduces hiss but, some people feel, takes away a bit of the sound’s high-frequency character. This feature can usually be turned on or off, however.

MTS. Never heard of Multichannel TV sound (MTS)? You’ll probably be sick of hearing about it by the end of the year. Basically, it’s the growing capability of stations to broadcast stereo audio (plus an extra audio signal that can be used for translation or other purposes). More than 200 local stations are equipped for stereo, and NBC and PBS broadcast several hours in stereo per week. The Federal Communications Commission approved the MTS system two years ago, and now selected programs are broadcast using it, with more sure to be added. Some cable channels also send out a stereo signal, but not all are MTS (and not all cable companies relay the signal on to their subscribers, so a call to your own cable company before investing in MTS is advisable).

Since MTS uses a special compressed-signal method, its quality is superior to FM stereo. To receive and record these signals on your VCR, either your television or your VCR must be MTS-equipped. If you’re buying both a new VCR and a new TV in the near future and want this added-cost feature on only one of them, the television is preferable.

Buying a VCR that’s hi-fi/stereo without MTS? You can add an MTS decoder later if your VCR comes with an MPX jack, but this costs extra and you’ll have to get exactly the right decoder for your set or the sound won’t be satisfactory.

Monitors. It isn’t considered chic to call top-of-the-line TV sets “TV sets.” Now, they’re “monitors.” Monitors are TV sets with special features. Among them: inputs and outputs for cable, VCRs, computers and other uses, and stereo capability.

It’s important to distinguish between two types of stereo capability: Some monitors have MTS while others are only “stereo-ready,” and that means they have an input that will accept an MTS decoder for which you’ll have to pay extra.

So, if you want to immediately receive stereo broadcasts and can’t or don’t want to operate from a VCR-with-MTS tuner, make sure the monitor you buy has MTS. MTS-equipped models have built-in receivers, so that you can plug in speakers directly.

If you do plan to have a VCR with MTS but not a TV with the feature, be prepared to live with the fact that you won’t be able to receive stereo broadcasts unless your VCR is turned on and the TV is operating off the VCR tuner--which it will only after the “play” mode on the VCR has been activated.

Just remember: Even if you invest thousands of dollars in a new TV and VCR, the quality of what you hear is still going to depend on how good your speakers are. So if your woofer isn’t woofing very well, get ready to lay out even more cash. It’s a brave new world--and an expensive one.

LIVE AID VIDEO: This week’s Home Tech question comes from Allison M. Goldman of Los Angeles, who asks, “Are the Live Aid concerts which were held in July, 1985, available on videocassette?”

A spokesperson for Rogers & Cowan, the public-relations firm representing Live Aid, said that there are currently no definite plans for a Live Aid video, though that does not rule out the possibility of one in the future.