Last Saturday I turned on my FM radio to listen to the Texaco broadcast, live from the Metropolitan Opera in New York, of Giuseppe Verdi's "II Trovatore." The gypsy Azucena was weaving her wiles when I tuned in and I was ready to be led wherever Verdi wanted to take me, and then I heard a hum. No, more like a beep. Not like somebody was trying to get everybody in tune, more like somebody was broadcasting bad breath: beep-beep-beep-beep. I checked another FM radio in my apartment and got the same beeps. I called the radio station, WGMS.

Yes, the announcer allowed, he knew there was omething wrong. Ten other listeners had complained. There were complaints every week. WGMS was not at fault. The root of the evil was the decision by Texaco to stop broadcasting in stereo and instead use a cheaper monaural connection from New York to Washington.

Back to the opera, back to the beeps - then it hit me that this was the Metropolitan Opera, distorted to the point of displeasure because Texaco, an Oil Giant, wants to save money! I began troubleshooting. First to stop the beep, then to learn why the opera lost stereo. The WGMS announcer gave me a half-dozen numbers to call. While opera quiz giggled on, I investigated.

WGMS program director, Mike Cuthbert, explained the setup. Forget about radio waves beaming up from the Met and bounching off the ionosphere into your radio. The music comes down on ATT program lines. All lines are not equal.

"Last year we had a 15-kilohertz stereo line from New York," Cuthbert explained. "This year they gave us a 5-kilohertz monaural line. We've complained. Philadedphia has the same problems and they're complaining.

But the people who produce the show for Texaco, the G.H. Johnston Co., haven't done anything about it."

"You mean with this cheaper line there's more likely to be problems with beeps?" I tried to sort out the kilohertz.

"Yes."

The Met may be the best opera house in the world, but on Saturday afternoon most people were hearing it via the cheapest facilities. And Cuthbert had a theory that went beyond mere economizing by an oil giant. "National Public Radio is out to get the Met Broadcasts, and this poor quality service may have something to do with somebody trying to make people unhappy with commercial stations like WGMS."

A conspiracy theory! But meanwhile the beep continued. Surely a mere 5-kilohertz line should carry opera without a beep. Cuthbert admitted that only in the last four years did they have stereo, before that the broadcast was always on the monoline - the same type of line that carries TV audio.

John Strohllo, an ATT technician at the program operations center in New York, hadn't heard of any problems with a beep.

"There should be no beep on a 5,000-cycle line," he averred.

I called the announcer at WGMS and he assured me he had complained to ATT Washington.

"I haven't heard about any complains," an ATT technician in Washington told me. "But I just came on duty.Let me check with my supervisor."

And the supervisor told him to tell me to call ATT eastern regional office first thing Monday.

OK, but meanwhile: beep-beep-beep.

Quite frankly, when ATT said there was no trouble, well, I began doubting my ears. Cuthbert mentioned that Philadelphia had been having trouble with the broadcast, so I called station WFLN.

"We've had hundreds of complaints since this season's broadcasts began," WFLN announcer Paul Mason explained. "This is the quality sound you got with the old Toscanini broadcasts in the '40s. We don't have a beep like you're hearing, but hte sound is just bad. I used to work news and this sounds like a Saigon feed. I have a hunch. I wonder if somebody wants this sound bad to stop people from taping these broadcasts at home?"

Another conspiracy theory!

But in my ears still beep-beep-beep.

Since Philly had no beep, it must be a Washington problem, or I was getting myself ready for the mad scene from "Lucia." I called an opera buff in town. She was taking a nap. I woke her up. She turned on her radio. "I don't hear any hum or beep."

I groveled back to my radio; the beep was gone! Bewildered, she went back to her nap.(Often in these affairs it's the innocent bystander who suffers most.)

By rights, I deserved to enjoy the last act of the opera, but was there a conspiracy afoot! Was an Oil Company cutting corners with Art! And then, why did the beep (if it was there!) go away!

I called ATT Washington.

"It stopped? Well, we didn't do anything. Did you adjust your antenna?" replied a chap with a etchnician's insolence. I put him back in his place. "Well, we didn't do anything. We're just been watching the basketball game."

An hour after the opera ended I got a call from G.H. Johnston himself. The producer since 1952 of the Saturday broadcasts took time out of his vacation to respond, and it went like this:

"We cut back to 5,000 because we had nothing but complaints with stereo for four years. It was experimental, and we gave it to 11 cities on the East Coast. But the guy in Phoenix, he wanted stereo too. So we got nothing but complaints. Personally I don't listen to music in stereo. Beethovan didn't write music in stereo. It's not natural to hear Pavarotti in one ear and Sutherland in the other. Except for the last four years, the broadcast was monaural and we never got complaints. And the only area complaining now is Philadelphia!"

I asked him if Texaco was just economizing.

"I wish I had the money it takes to produce this broacast. You wish you had it! It's a lot of money, 21,000 miles of lines. Look, I know Texaco is not chintzy. What's going on is that people are after the oil companies. Kennedy, Johnson were after the oil companies. So is this Carter. Texaco people are good people. They're not chintzy, I know."

Was this a ploy to push the opera broadcasts over to National Public Radio?

"Texaco won't give it up. That's what's behing these complaints in Philadelphia. They want to take it from Texaco and give it to Public Radio. Look, why is it that only these folks in Philadelphia are complaining?

You can't help liking G. H. Johnston. I'll never listen to Beethoven in stereo again.

I called Philly, and Mason assured me the complaints came from genuinely anguished opera fans.

I checked with WCRB in Boston, and station vice-president Richard Kay complained: "They went back to the monaural line and the quality is bad. We told them that if it didn't improve we would drop the broadcasts. Today, we had trouble with volume. We had the beep you mentioned another week (cancel that appointment with the ear doctor!!). Service provided by ATT is not very good either. People expect improvements, not a step backward."

By bedtime Saturday I had sorted it out: beeps in my ears, a volume problem in Boston, general discontent in Philadelphia with conflicting conspiracy theories as to motivation (note: New York, Universal Capital of Complainers, still gets the broadcast in stereo). In addition, I uncovered allegations of poor service against ATT. Intimations that Texaco had gone cheap. And during the Sabbath I heard from another opera buff, who said that in his opinion the broadcasting quality is terrible and the reason is that the singers want to make us buy their records and not tape them from the broadcast.

As Monday dawned, I tackled the task in reverse order. "That's nonsense!" replied a spokeswoman for the Metropolitan Opera when asked if singere were behind the poor broadcast quality. "It's silly." (If you're reading this out loud her accent if British.) "People like Renata Scotto would feel dreadfully if they knew the sound was bad!"

And, by the way, they'd no complaints about the quality of the broadcast.

A spokesman for Texaco noted that costs have been going up. Unions, the Met, ATT, engineers, radio stations, etc., all want more. In addition, Texaco had to spread their budget to include the live television broadcasts from the Met.

Cleveland and Detroit still get the broadcast in stereo. ATT simply doesn't have a stereo line to D.C. for the right price.

Texaco believes, however, that the monaural line should provide adequate service. They sent an engineering van to Philadelphia to see what the problem was down there. Out in Long Island the monaural broadcast sounds fine. For years the broadcast was in monaural, and back in 1972, 69.2 per cent of listeners surveyed said the broadcasts were excellent; nobody said they were poor.

As for NPR, indeed, they come to Texaco and ask for the broadcasts. But Texaco is going to stick with commercial stations. Finally, a solution to all th problems is in the future. A satellite will soon go up over the East that will allow nation-wide stereo broadcast of the Met.

The highpoint of the interview was when the spokesman for Texaco allowed that "service from ATT is not always the best."

Pic Wagner of the ATT Long Lines Division took the sniping at his corporation in stride: "We handle a large volume of traffic and we do our best to maintain the highest quality. We can't monitor all th audio lines because there would be 20 going at once and the technicians would hear nothing but babble."

Except when Pavarotti hit a high-C, I should think. And maybe during time-outs in the basketball game on TV a technician could give a quick listen to the Met.)

But Wagner had more than excuses. He had the answer: "Last Saturday the usual program channel that is used for the opera was in use and was not available. We used and alternate facility and for a half-hour there was noise on that channel. We then re-routed the opera to another channel."

"Voila. The third act was without a beep. And I might add it was much longer than a half-hour of noise.

Modestly I asked if my complaining might have sparked the rerouting of Verdi. Wagner didn't know. But he did have some good news. "Starting with the January 28 broadcast the Johnston Company has ordered 15-kilohertz lines for Philadelphia, Baltimore and Washington."

I called Texaco to see if it were true. Texaco hadn't heard about it. I called the G. H. Johnston Company, and they confirmed what ATT said. I knew G. H. Johnston, foe of stereo and Philadelphia, still had a big heart. It will be a 15,000 mono line; no noise and no phasing problem.

So join me in front of the radio today for Wagner's "Tannhauser" pulsing down through 5,000-hertz lines. Then next week and thereafter it's Massenet's "Thais"! at 15,000! Hear what a difference 10,000 cycles will make! Which orgy will sound better? Viva la difference!