Mar 1, 2002 12:00 PM, BY PAUL D. LEHRMAN

Note to readers: An active discussion on this topic, which includes information about the musicians' earplugs I mention in the article, is underway in the Talkback section of Mixforums.com. Anyone can read the posted messages, but if you want to add to the discussion, you must become a member of Mixonline. Membership is free, and takes only a minute. See you there! -- Paul Lehrman

What do you call it when you hear noises that aren't really there? No, I'm not talking about what happens when you drink too much, or when all that LSD you swallowed years ago flashes back at you. I'm talking about the whistles, rings, whooshing sounds and other aural artifacts that are associated with a head injury, high blood pressure, or taking certain medications (like aspirin), or hearing damage. It's the condition known as “tinnitus,” which doctors like to pronounce “TIN-uh-tis,” while the rest of the world says “tin-EYE-tis.” With tinnitus, the ears seem to be picking up sounds that don't exist externally. It takes many forms and has many, many causes. There was an excellent article on the subject by Bob McCarthy in the January 2001 Mix, and if you're interested in the subject, you should go back and take a look at it (of course, it's on mixonline.com).

About a year ago, all of a sudden I got very interested in it, because all of a sudden I got it. And I also got pretty scared.

For most of my post-adolescent life, I was quite sure I had escaped the fate of so many of my fellow '60s and '70s rock 'n' rollers, managing to avoid any damage to my hearing from years of playing in and listening to bands that were, let's face it, too damn loud. These days, at the levels I typically listen to music, both for pleasure and for business, it seems unlikely that I'm going to do anything further to screw up my ears. The bulk of my studio work is film scoring, and I usually work at relatively quiet levels, because I figure that's the way it's going to end up anyway when the mixing guys are done with it.

But about a year ago, I had a chance to do a score for an old silent film, and a pretty raucous score it was. I spent several days on it, monitoring at uncharacteristically loud levels. One day, after a few hours of sitting in one position, my back started to hurt a bit, so I did what I always do under such circumstances: I got up, took a long stretch and walked over to the bathroom to get a couple of ibuprofen. That night, before I went to bed, I popped a couple more of the pills, just to make sure I wouldn't have trouble sitting through the next day's session.

Imagine my surprise when I awoke in the morning and discovered my ears were ringing. Well, actually they weren't ringing, but something inside of them seemed to be. It sounded like a sine wave generator up at around 8 kHz or so, and it was in both ears and quite constant. Imagine my further surprise when the ringing lasted all day and into the next. Whenever this happened to me before — usually because I was at a really long, loud concert, without any ear protection, something I haven't done in years — it never lasted more than a couple of hours.

Was it the ibuprofen, which, like aspirin, can cause a ringing in the ears, or was it the unusually high levels that I'd been listening to? Or was it the combination of the two or some other medications I had been taking? But the real question, the one lurking underneath all the others, was: Had I done something to myself that had permanently damaged my hearing?

Let's step back a minute. Like most folks past 30, especially men, my hearing is not as acute as it once was. When I was working in the electronic music lab in college, I would often test myself, seeing how high I could get the old Heathkit oscillator to go (without looking at the dial) before I couldn't hear it any longer. It was usually, I was proud to see when I turned around, up around 22 to 23 kHz. When I worked in radio a few years later, I was the only guy in the place who could hear the 20kHz track on the Magnetic Reference Laboratory Reproducer Test Tape. And for a long time, I could walk into any room — heck, any house — and tell you if a television set was on, because I could hear the 15,750kHz whistle that the fly-back transformer made.

But as we get older, our high-frequency hearing drops off. It's normally an extremely gradual thing, so we don't notice it. One day in the '80s, during a period when I was reviewing a lot of high-end recordings for consumer magazines, I was checking out my system with a test CD and discovered, to my dismay, that I couldn't hear the 20kHz band. A few years later, I realized that the only way I could tell if a TV set in a room was on was to look at it. And for some reason, I can't hear my wife as well as I used to when she shouts from her office on one end of the house to my office on the other end. I don't think it's because our house is growing bigger.

Fortunately, I really haven't had too much trouble resigning myself to the fact that, like sliding head-first into home, diving from the 5-meter board or hitchhiking up the East Coast, hearing 20 kHz was just one of those things I was never going to do again. My hearing perception, on the other hand, seems to have improved over the years, which makes sense. Although being able to hear high frequencies is certainly an important part of it, aural perception is very much a product of knowledge, smarts and experience, which is why there are plenty of guys well into their '60s who are still great mixing engineers. Maybe I can't hear the sampling clock on a CD player, but I can still tell you who's playing the wrong note in a 20-piece big band, or at what bar the drummer is coming in just a hair late, or exactly where to set the mid-band EQ to bring the vocal up out of the mud. And I think I can do all of these things a lot better than when I was younger.

So you can see why I might be terrified when the sudden noise in my ears wouldn't go away. After the second day, I called my primary-care doctor, and he said it was probably the fault of the ibuprofen and the noise would go away in a few days. After a week, when it was still going strong, I called another doctor, a pharmacologist. She said it probably wasn't the drugs, but the result of all that loud music I'd been listening too, and if I was lucky, it would go away in a few more days.

But it didn't. After two weeks, I was beginning to get really nervous. I started stuffing my ears with cotton whenever we went to hear any amplified music, which made me feel worse, because the music sounded so awful and the ringing actually seemed louder. Then I started plugging my ears whenever I got into the car. A fire engine would go by and I'd put my head down between my knees as if I was expecting a bomb to drop. After a month, my wife was ready to kick me out of the house.

I sent an e-mail to the Hearing Education and Awareness Foundation in Los Angeles, a group that specializes in treating musicians with hearing problems, and also happens to be one of the organizations that benefits from the TEC Awards banquet and other Mix Foundation activities. It has a great Website (hearnet.org) that lists affiliated hearing specialists all over the country. Unfortunately, there's no one on that list less than 100 miles from me. Fortunately, Kathy Peck, one of the two founders of the organization, e-mailed me back the same day and gave me the name of an audiologist at the Massachusetts Eye & Ear Infirmary, which (except in rush hour) is only about 15 minutes from my house.

I got an appointment right away (mid-afternoon) and met Dr. Christopher Halpin, a pleasant fellow around my age, who, as it turned out, was also an electronic music freak when he was in college. In between feeding me sine waves, recorded speech and various other types of noises through a pair of heavy headphones, he and I had a grand time talking about the bad old days of drifting oscillators, finicky 16-step sequencers, lousy speakers and roaring EMT plate reverbs.

Chris gave me a complete workup, and when it was over, he handed me a sheet of paper with the results. “Hearing is normal through 3 kHz,” it read, with “a very mild symmetric sensory loss above that.” “Typical for a man your age,” he said. “You're right in the middle of the range.”

The graph he plotted for me, with 1 kHz at zero, went down 15 dB at 4 kHz, 20 dB at 8 kHz, and 50 dB at 12.5 kHz. That seemed like quite a drop-off, and nobody I know would tolerate a microphone that did that, but he said it was perfectly normal for human ears. “What about above 12.5k?” I asked him. “Oh, we don't measure that,” he replied, “because there's no way for us to specify a sound pressure level as a reference point. At those frequencies, the waveforms get affected by the construction of the ear itself: You can get standing waves as small as the ear canal. Since everyone's ears are different, there's no way to tell objectively what's going on.” This took me rather by surprise, but I had more important issues to deal with.

Like, what the heck was causing my tinnitus? Chris' reply was that, while he couldn't tell what was causing it, he was pretty certain that it was not caused by my recent studio sessions. “If you've been listening for years and years at loud levels, I'd say that could be a factor, but one loud mixdown session isn't going to do it. Something like that might cause a temporary threshold loss, and maybe a ringing, which recovers in a couple of days.” Decades' worth of high SPLs, he explained, could damage the cilia, the frequency-sensitive, hair-like nerve endings that serve as our personal D/A converters; they literally break off. But that wasn't my problem. If I did have any hearing loss, and it wasn't at all clear if I did, it was more than likely due to genetic factors. My grandfather, after all, was stone deaf by the time he was 50. “But none of these factors are strongly related to tinnitus,” Chris said as he shook his head. “Really, tinnitus is not an ear thing at all — it's a phantom percept.”

After I gave him a hug, he suggested that if I wanted to learn more about tinnitus, and maybe pin down the cause, I should make an appointment in the same hospital with Dr. Robert Levine, an otoneurologist (“oto” means “ear”), who is recognized as one of the world's tinnitus experts. Before I left the clinic, I bought a pair of musician's earplugs for $25 that he recommended. Now I didn't have to carry cotton balls around with me, and I could go into a club and still hear the music, without worrying about frying my cilia.

Dr. Levine's office, to my dismay, told me he only saw patients one day a week, and he was booked solid for six months. I made an appointment anyway and told the secretary that if anything opened up (not during rush hour), she should call me. Three weeks later, after someone had canceled, I was sitting in Dr. Levine's office. And I found out why he was so hard to see: He ended up spending almost two hours with me.

Dr. Levine is a researcher as much as a practitioner, and his mission is to find out how tinnitus affects people. He asked me all about my ethnic background (which was almost identical to his, it turned out — we could be cousins), medications I was taking, past injuries and operations, family medical history, the nature of the sound I was hearing and dozens of other questions. I noticed that his office seemed to be rather noisy, and I looked around for the source of the sound: There was an object on the floor, about the size and shape of a small birthday cake, which was emitting a sound like rushing water. It was a sound masker — an acoustic dither generator. He saw my glance and smiled. “I have it, too,” he said.

He cataloged some of the many causes of tinnitus. Besides exposure to loud sound, there are ear infections, wax buildup, benign tumors, drugs (a common sedative, alprazolam, can, in different people, be the cause or the cure for the condition), and stress: physical, biochemical, environmental or emotional. He moved my head, arms and hands into various odd positions and asked me whether the sound changed. He was delighted when I reported that sometimes the pitch of the sound changed, and that sometimes the level changed. Apparently, very few of his patients can tell (or articulate) the difference between the two.

I was delighted when I discovered that if I locked my fingers together in front of me and tried to pull my hands apart, the intensity of the sound would diminish noticeably. Not that I could walk around all day like that, but it meant I could feel that I had at least a tiny bit of control over the thing.

So, after two hours, what did this leading scientific authority have to say about what was causing my problem? He shrugged and said that he really had no idea. The good news was, he agreed with Dr. Halpin that it didn't have anything to do with the sound levels I had been subjecting myself to. The bad news was that, although he thought it might go away by itself, “I wouldn't want to bet on it.” He suggested getting a noise-making machine like his, or keeping music going in the background all the time. And he did have one optimistic thing to say: “In three months, you'll hardly notice it.”

He was right. I still have the noise in my head a lot of the time, but I really only notice it occasionally, and it rarely bothers me. (Although, at the moment, because I'm thinking about it, it's pretty loud.) But the whole experience of learning about tinnitus and what audiologists know and don't know has actually brought to my mind a whole new set of questions. Is research in audiology so far behind what we in the audio profession consider to be current state-of-the-art that we know more about how frequencies in the top octave of our range are supposed to behave than audiologists do? What happens if you look at it the other way around? How important is it really that our signal chains be dead flat up to 20 kHz, because most of us can't hear anywhere near that high, and audiologists can't measure how we respond to those frequencies? And what about the world above 20k? What is its role in the way we perceive music and sound — if it has any?

I've started pursuing these questions, and I've been coming up with some surprising answers, which I'll tell you about in a future column. In the meantime, keep your levels down and your ears protected.

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Paul Lehrman is a composer, educator and Mix's online editor. His personal site is paul-lehrman.com. He can be reached at mixonline@gis.net. Join a discussion about tinnitus at Mixforums.com.

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