I once wrote that FM systems were the most significant educational tool developed for hearing-impaired children since the advent of group and personal amplification devices (Ross, l992). I still think this is a valid observation. FM systems, in all their various permutations, remain the single most effective way of increasing the speech to noise (S/N) ratio, perhaps the most important factor underlying speech perception performance. And, crucial as this can be for adults, it is even more important for hearing-impaired children who are in the process of developing speech and language. The most efficient and natural route for learning an auditory-based linguistic system is through the ears. In maximizing the S/N, we are providing children with the best possible auditory-verbal exposure in a particular experiential situation. These acoustic/linguistic stimuli are the raw materials that nourish the children’s brains as they make the associations between auditory signals and ongoing events. We know that children are much better learners of language than we are as teachers (listen to young normally hearing children!), if we can but provide the appropriate conditions. This is what an FM system is designed to do, i.e., to provide more of the essential ingredients for fostering and stimulating linguistic growth. In brief, the FM system is more than just an interesting and useful device: it is an essential educational tool for hearing-impaired children. Since FM systems were first developed for use by children, I would like to start by briefly reviewing the situation that existed prior to their introduction, talk a bit about the early history, and then discuss the major advantages they offer to for adults as well. In doing this, I hope readers will forgive me if I draw heavily on my own publications and experiences. It is not only that I know these best, but that my own career has been so intertwined with developments in this area that a review of the early history of FM systems necessarily involves much of my early professional background. In addition, because I’ve worn hearing aids throughout my professional career and have frequently used FM systems, my personal experiences (and views) also seem relevant.
Personal FM systems were first introduced for use by hearing-impaired children in the middle and late l960’s. I understand that it all began about 1963 with a company in New Haven called Electronics Futures Inc. (Parente 2003) that developed an AM radio system as an auditory enhancement device for use in classrooms. The system transmitted a low frequency, low power AM signal from a wire antenna looped around the room. The children used large belt pack AM receivers and headphones. For some of the smaller kids, the receivers and headphones seemed almost as big as they were! The teacher plugged a microphone into a fixed AM transmitter, thus restricting her movements to the length of the microphone cord. Only the children could move around freely. This system didn’t last very long. A few years later, the company introduced a completely portable FM microphone transmitter, one that permitted both the children and teachers freedom of movement. As I recall, the system worked pretty well (though the receivers and transmitters were large by current standards) but it never caught on and by l972 the company was out of business.
The Phonic Ear Company introduced its system about l967 or l968. Their initial system used the commercial FM band 88-l08 MHz (Pimentel 2003). As can be imagined, the children picked up lots of extraneous radio signals on this band. In order to overcome interference and to transmit an acceptable signal, the company found it necessary to exceed the power limits permitted by the FCC (an early example of “civil disobedience”?). But its systems were completely wireless and portable, for both the children and the teachers, making the educational advantages self-evident. The FM microphone/transmitter was suspended from the teacher’s neck with about a two-foot antenna hanging below it. The receiver was not much larger, though thicker, than a body hearing aid.
To bypass the limitations imposed by the 88-108 MHz band, and since the technology had already proven its importance to children in classrooms, the company helped initiate a letter writing campaign by parents, teachers, and other professionals asking the FCC to designate a different portion of the radio spectrum for wireless FM devices. With parents, in particular, making a convincing case to various members of Congress, these efforts were ultimately crowned with success. In l971, the FCC allocated the 72 to 76 MHz band for use with audio enhancement devices for hearing-impaired people. Much later, of course, the 216 to 217 MHz band was added which, because of the smaller wave length, offered many additional technical advantages.
As it happens, FM systems arrived on the educational scene in the nick of time. Prior to their introduction, classroom systems were either hard-wire devices or induction loop systems, supplemented by whatever personal hearing aids the children wore. The typical hard-wire system consisted of a single microphone, an amplifier, and a junction box at each seat into which a headphone was plugged (see figure 1).
Figure 1. A hard-wire classroom amplification system.
Note that both the teacher and the children are too far from the microphone
for optimal self-monitoring, child-to-child communication and reception
of the teacher’s speech (picture courtesy of Brad Ingrao).
This arrangement rarely provided children with an optimum amplified signal. The location of the microphone usually precluded an acceptable speech to noise ratio, either from the teacher’s speech, self-monitoring by the children, or effective child-to-child communication. If it was close to the teacher, then the children could not hear themselves or the other children when they spoke. (When I once pointed this out to the principal in a school for the deaf, she told me that “it is against the school policy for the children to hear themselves when they speak”! At which point, I became speechless.) If the microphone was located close to the children, the quality of the teacher’s speech suffered. If it were located between the teacher and the children, then all verbal signals were somewhat compromised (as is shown in figure 1). Then there was no individualized tailoring of the amplified signal, except for a volume control that the children could use if they wished. Earphones were interchangeable and the children used the one at the seat to which they were assigned in the various classrooms. I often listened through the earphones at the VC setting used by different children and rarely heard what I would consider to be an acceptable amplified signal. For the most part, they were either too weak or distorted.
The other classroom amplification system, introduced just prior to the advent of personal FM systems, was induction loop (IL) systems. The main advantage of this system is that it permitted the children freedom of movement in the classroom, although the teacher’s movements were still restricted by the microphone cord (see figure 2). After IL systems were introduced, it took several years for audiologists, teachers and engineers to identify and correct the problems that were noted. These problems included: the specific positioning of the telecoil within the hearing aid; the lack of an M/T position that would permit the children to self-monitor and to hear the other children; magnetic field spillover into adjacent areas (never completely solved); and ensuring an adequate and equal magnetic field throughout the looped area (Ross 1969). By the time these problems were identified and corrected, FM systems had arrived and proven their value. This is when the use of IL and hard-wire classroom amplification systems began to decline. (We should note, on the other hand, the recommended resurgence of IL systems with adults (Ross 2002; Myers 2002)).
Figure 2. An induction loop system.
Note that the teacher’s movements are restricted because of
the microphone cord (picture courtesy of Brad Ingrao).
Fortuitously, the FM era began at the same time that professionals were being faced with an inundation of young hearing-impaired children, as a consequence of the maternal rubella epidemic in late l964 and l965. Suddenly society was confronted with the necessity of providing appropriate services to many thousands of children with varying degrees of hearing loss (as well as many other problems). Because of the sheer numbers of children who now had to be served, the deficiencies in available technology, educational programming and facilities soon became very apparent. My personal experiences as I visited and consulted in a number of pre-school programs during this period exemplifies this point.
A great many pre-school programs were organized as the rubella children reached three and four years of age. These programs were situated in whatever large space could be made available, most of which displayed horrendous acoustical conditions. Almost invariably, all the surfaces in the room were wood or concrete, with no attempts made to reduce the consequent reverberant effects. I visited and consulted in many of these programs and I often found that I could not understand a teacher speaking just a few feet from me if the children were engaged in noisy activities around the room (and when were they not?). To carry on a conversation, I often would have to ask if we could adjourn to the hallway or to another room. And if I, with an excellent command of the English language could not understand the teacher, how could the children be expected to develop an auditory-verbal based language system? To answer my own rhetorical question: not very well. The children were being deprived of the salient auditory linguistic exposures necessary to best learn language. In many of these programs, about all that one could hear through hearing aids was noise, with a bit of the speech signal peeking through now and then. The children were being forced to depend primarily on their vision for communication purposes.
While this period (l967-1970) may seem like the Middle Ages to some current readers, even then we really did try to fully utilize the children’s residual hearing. (For a history of amplification with hearing-impaired children see Ross l996.) However, the physical settings in which most of these children received their initial educational exposure made this goal impossible. In most pre-school programs, the children were using body hearing aids. (We recommended binaural body aids worn in a special harness on the child’s chest.) They could receive amplified sound, of course, but the deleterious impact of the acoustical conditions markedly reduced the effectiveness of hearing aid amplification. Sometimes it seemed that our educational management and settings were designed to create functionally deaf children from those who were potentially hard of hearing. Still, we did our best.
The dilemma we faced is well illustrated in a table I developed for the first edition of the Handbook of Clinical Audiology (Ross l972), in a chapter on “Classroom Acoustics and Speech Intelligibility.” The table includes all the studies that measured speech perception scores as a function of distance from the source, in both acoustically treated and untreated rooms. Note that in every example, the closer the listener was to the source of sound, the higher the scores. Some studies compared speech perception scores in both acoustically treated and untreated rooms. Here also, higher scores were obtained in the treated rooms. Currently, we would hardly consider these observations to be particularly noteworthy. Now, of course, we know that when we reduce the distance from a sound source to a listener or microphone, we increase the S/N and thereby improve speech perception capabilities. The same phenomenon occurs when the noise levels are reduced through acoustical treatment. But it is interesting to note that except for one of these studies (Miller and Niemoller 1969) all the others were done in countries other than the U.S. At the time, classroom acoustics and its impact upon speech intelligibility in classrooms hardly registered as an important factor in our curriculum or professional practices. It was just not something we thought about or conducted research on. So what is obvious now was not so obvious 30 years ago. We have made progress.
| Distance from Source | ||||||||||
| Investigator | 3" | 6" | 12" | 18" | 3' to 4' | 5' | 9' to 12' | 14' to 15' | 22' | Subjects |
| John & Thomas (1957) | 96 | 94 | 77 | 70 | 68 | Normal hearing university students | ||||
| Dale (1968) | / 84 | 54 / 78 | 44.8 / | 39 / 64 | 12 partially deaf children | |||||
| Watson (1964) | 84.8 | 35.2 | 19 partially hearing children | |||||||
| Watson (1964) | 98.6 | 53.3 | Normal hearing adults | |||||||
| Watson (1964) | 91.8 | 28.3 | Partially hearing adults | |||||||
| Fisher (1964) | / 87.3 | / 68 | 54 / 57 | 42 / 50 | 9 partially hearing children (monaural) | |||||
| Fisher (1964) | / 98 | / 82 | 65 / 81 | 44 / 59 | 9 partially hearing children (binaural) | |||||
| Miller & Niemoeller (1967) | 25 / 34 | 4 / 28 | One elderly Meniere's patient | |||||||
| Ross & Giolas (1969) | 59 | 32 | 13 hard of hearing children | |||||||
Table 1. Speech perception as a function of distance from the source.
Figures under the slash show scores obtained in acoustically treated rooms (Ross 1972).
When FM systems were introduced, they seemed like the answer to our dreams. Here was a way of transmitting the teacher’s speech almost directly from his/her lips to a receiver worn by the child. The negative effect of the acoustical conditions existing in the room could be reduced, if not completely eliminated. The systems permitted complete mobility by both the children and the teacher. They could also be used one-on-one – one teacher to one child – making the provision of acceptable amplification in a regular school program feasible. Thus, “mainstreaming” became a viable educational alternative. This meant that many more children with hearing loss could be educated in their local schools alongside their friends from the neighborhood.
We should understand the implications of this development and the educational revolution it helped foster. Up until that period, across the country, there were essentially only two choices available for children with hearing loss: either a residual program at a school for the deaf, or full mainstreaming in the neighborhood school. If a child could not be satisfactorily educated in a regular school, which was true of many children with moderate and severe hearing losses, he/she was sent off to a residential program (only a relatively few day programs existed then). Too often these kids were considered to have “failed” in the regular school when the reality was that their neighborhood schools had failed them. But the only hearing-impaired children that local schools had any experience with were those with mild or (some) moderate hearing losses, many of whom did not even wear hearing aids.
Still, many parents were adamantly opposed to enrolling their child in a residential program; they wanted their children at home. As it happens, the children coming out of the Rubella epidemic generally had more severe hearing losses, requiring effective amplification as well as an organized program of supportive services (such as tutoring, speech and language therapy, etc.). They could not “make it” on their own without this extra help. Additionally, the acoustical conditions that then existed in the regular schools made listening through hearing aids a difficult task (Ross l992). There was no way a child could receive an satisfactory signal in a classroom with reverberation times of 1.2 sec or more and ambient noise levels just a few dB weaker than the teacher’s speech. This meant that relatively few of these children could fully utilize their residual hearing in a mainstream setting and thus would be unable to obtain a satisfactory education in such a setting.
In Connecticut, we started recommending personal FM systems for children in 1968. At that time almost every child we fit was either already mainstreamed or headed for the mainstream upon completion of a pre-school program. The results we observed with the children we fit convinced us that personal FM systems deserved widespread use throughout the country. To help corroborate our informal observations, we (Ross and Giolas l971) conducted the first published study that compared the speech perception performance of children using an FM system with the performance with their own hearing aids. As I read it now 32 years later (the study was actually completed in l969), the results and conclusions still hold up; moreover, they have been verified by other, more sophisticated later studies on the same topic. It is of interest to briefly review this original study now.
What we did was administer PBK 50 word lists via monitored live voice in a regular classroom to 13 hard of hearing children with mild to moderate hearing losses. Seven of the children normally wore hearing aids and six did not. All the children were fully enrolled in the local school district. They were seated 12 feet from the examiner and the S/N at their location was plus 5 dB. We covered our mouth with cheesecloth so that the children could not observe our lips. As they heard each word, they were required to write the responses down on prepared answer sheets. We were primarily interested in comparing the children’s performance with the FM system to their usual listening situation in the classroom (aided or unaided). We also tested a control group of 18 normally hearing peers to determine what their speech perception scores would be in the same classroom and under the same conditions. The usual experimental controls were practiced (counterbalancing, practice list, multiple scorers of the child’s responses, etc.).
The results clearly supported the value of FM amplification in the classroom. In the children’s usual listening condition, the overall word discrimination score was 32% (as compared to the 91% achieved by normally hearing children in the same classroom). With the FM system, however, these children achieved an average score of 59%. While this still indicated a major problem understanding speech in the classroom, we believed that an increase of 27% in speech discrimination scores could have significant educational benefits.
[Nowadays, of course, we would hardly be satisfied with FM aided scores of 59%, not with the mild and moderate nature of the children’s hearing losses. Nor would we have to be. Currently, FM systems have built-in capacities that even the finest hearing aid on the market at that earlier period did not have. At that time, FM systems were really primitive devices. They accomplished the crucial task of providing an enhanced signal to noise ratio, but that is all they did. There were no controls for modifying the electroacoustic characteristics of the FM signal. Except for volume control adjustments, children whose hearing losses varied considerably received exactly the same pattern of amplification.]
We felt that these results were very encouraging and that they called for more aggressive recommendations of personal FM systems by audiologists, and not just in preschool and mainstream settings but wherever deaf and hard of hearing children were being educated. But this was just one study that could be easily ignored or discounted. So we did it again, two years later, in the same school building. Nine of the original children were included in the total of 11 subjects in this second study (Ross, Giolas and Carver 1973). We followed essentially the same procedure as in the previous study, but without the control group. Nine of the children used hearing aids (four monaural and six binaural). Our purpose again was very straightforward: We were interested in comparing the scores obtained in their usual listening situation with those achieved when they employed an FM system.
This time the children scored an average of 22% in their usual listening situation compared to 58% when they used an FM. Quite clearly there was no improvement in their “usual” listening situation. The 36% improvement produced by the FM system was similar to the 27% improvement obtained in the previous study. The speech discrimination scores of every single child increased in the FM condition. Some of these improvements were quite dramatic. In the real world, they would make the difference between struggling to understand the words, but getting only part of the overall message versus clearly hearing the teacher’s speech. Or between being educated in that classroom versus just taking up space. The results for the individual children are plotted in figure 3.
Figure 3. Word discrimination scores obtained by hard of hearing children in their usual listening condition compared to those obtained when they used an FM system (Ross, Giolas & Carver, 1973).
Looking at the scores in their usual condition, one wonders how the children managed to keep up with their classmates. Probably they did not. We have ample evidence of the poor academic performance of hard of hearing children in regular schools (Ross 2001) during those years (hopefully, better now). This reflects no lack of intelligence or dedication on their part, but simply the difficulty they experienced in hearing their teachers. And, to be specific, there is little doubt but that the academic performance of these 11 children would have been much improved if they had had the advantage of FM amplification.
This second study was published thirty years ago. In my naiveté, I had assumed that these results would stimulate an educational revolution for hard of hearing children, that in just a few years most of these children would be using personal FM systems in school. Well, it took more than a few years, but thirty years later I think (or hope) that we’re almost there. By now, FM technology itself is widely known and generally accepted. However there are still too many children who could benefit but are still not using FM systems, sometimes because they aren’t made available to the children and sometimes because they choose not to use the FM systems. For the reluctant students (particularly those in high school), to be visibly “different” from their peers is a fate worth than death. This is a very real, dilemma: How do we convince them that the stigma they perceive is mostly in their heads? (But we haven’t done very well with adults who need hearing aids either, and they are presumably more mature.)
Some years ago Carol Flexer showed us that it is possible to move reluctant hard of hearing college students, at least, from refusal to acceptance. She brought together a group of these students, all of whom had previously refused to consider using FM systems in their classes. In the group situation, she was able to convince the students of the value of FMs. She worked with them in a “protected” environment, demonstrating the effectiveness of the systems, until they fully accepted the use of FMs in most of their classes. The most convincing testimony, Carol says, came not from her but from students who had tried and personally experienced the benefits these systems conferred in the classroom.
One way to finesse this issue with many children with lesser degrees of hearing loss is to amplify the teacher’s speech for all the children in the classroom. Those wearing personal systems can tune their FM systems to the same frequency as the classroom system. Our “normal” classrooms are full of children for whom English is a second language, who are suffering from a temporary middle ear problem, or who have abnormal difficulty in processing speech for one reason or another. As an enormous amount of evidence now demonstrates, all of these children can benefit from an increased speech to noise ratio (as reviewed in Crandall, Smaldino & Flexer 2004), which is what classroom amplification systems (both FM and IR) are designed to do.
It may sound simplistic, but what these classroom systems have demonstrated is that we shouldn’t take hearing for granted. Until relatively recently, it was only people with hearing loss who were presumed to benefit from some kind of auditory enhancement device. And of course they can. But the research evidence accumulated with classroom sound-field systems demonstrates the value of increasing the S/N for a great many “special” children in a classroom, including those with perfectly normal hearing.
Since the first study was completed on these systems over 20 years ago, there have been more than fifty additional ones testifying to their efficacy (Saarf , Ray and Bagwell 1981). In tests of speech perception and spelling, the “special” children in the amplified classrooms scored higher than comparable children in non-amplified classrooms. They also did better academically and attended to the teacher for longer periods of time. There are less “acting out” or “tuning out” problems with the children. These systems have proven to be a cost-effective way of reducing special education referrals and services. In one large school district such referrals dropped to about half of what they had been before the sound-field systems were introduced in most of the elementary classrooms (Flexer, 2003).
While classroom sound-field systems were initially designed for "special needs" children, experience has demonstrated that the normally hearing children in the classroom are also benefiting. Presumably, while these children have no difficulty understanding the teacher in an unamplified classroom, they are nevertheless able to do this with much less effort and more certainty in an amplified classroom. Clearly, even normally hearing children have to hear well in order to learn well!
As an additional bonus, the teachers’ responses to the systems are almost uniformly positive. They appreciate being able to teach all day without straining their voices. This is not a trivial advantage. In one large-scale study, it was found that 20% of the teachers suffered from some sort of active voice pathology, with 70% reporting voice problems in the past that had caused them to miss work and/or that impaired their teaching effectiveness. In two laryngological practices, teaching was the most frequent occupation identified, representing proportions of 20% and 16% of the total caseload. So, while classroom systems were designed to help “special needs” children - and there is much evidence to support this goal - it is apparent that the benefits to teachers as well as to other children should not be overlooked.
Right now, however, I think that sound-field amplification devices (both FM and IR) are where personal FM systems were thirty years ago. We knew these helped children with hearing loss and we had the evidence to prove it, but it took many years for the word to permeate to all levels of the educational structure. While there may be thousands of sound-field amplification systems out there now, they represent only a tiny fraction of the classrooms in this country. Think about it. Think about all the evidence we have that demonstrates that all kinds of children do better in amplified classrooms. Think of how it is possible to produce significant improvements in the educational performance of school children in our society with such a relatively small investment. Coupled to improved acoustical treatment in classrooms (and we can’t forget this essential ingredient), amplified classrooms can significantly improve the education of our children. The evidence is there: Now comes the difficult part of convincing budget-minded administrators and school boards of the merits classroom amplification systems.
The potential advantages of an FM system are not limited to children. Hearing-impaired adults can also realize a great of benefit from them. There are many occasions when adults require a boost in the S/N in order to improve their comprehension of a message. And although the technical sophistication of modern hearing aids is wonderful, none can improve the S/N as well as a close-talking microphone. Hearing aids, even with the best directional microphones, cannot pick up a signal from across the room or separate the signal from the ambient noise. An FM system can. Years ago, when FM systems did not exist, an adult had a hearing loss had no other option but hearing aids. If he or she couldn’t hear well in some situation, it was tough, but that was the reality. Now we do have an additional option.. Now it is possible for hearing-impaired adults to hear better in college classrooms, in meetings, on tours, and in many other listening situations, but this possibility does require a concerted effort on the part of the professional community if it is to be realized.
I understand that many adults resist the notion of a personal FM system even though the acoustic benefits are apparent and clearly demonstrable. I view this as one of the major challenges faced by the profession. As we evaluate the communication needs of our clients, it should be apparent who among them are potential candidates. These people, who likely know little or nothing about FM systems, should be informed of their advantages and be encouraged to try them. New developments in FM receivers and microphone/transmitters have made their use more convenient than ever. The availability of universal FM boots has made practical demonstrations of their efficacy easy to arrange. But we can’t convince our clients to try them if we are not truly convinced ourselves. That has to be the first step.
Of course, people’s objections can’t be ignored. Potential users often have cosmetic concerns or they may find the additional cost prohibitive. These objections are legitimate for that person and must be respected. Perhaps because of my personal experiences with FM systems, but I’ve never had difficulty in making a convincing case regarding their many advantages. I sincerely believe in their efficacy and I’m able to convey this. What has worked very well for me is demonstrating FM systems to groups of hard of hearing people. Invariably, after using one myself in situations where my role was that of a participant and not a professional (such as in an elder hostel or tours), someone’s interest would be piqued and I could demonstrate the effectiveness of the FM system. What I’m suggesting is the contribution that peer mentors can make in overcoming resistance to using an FM system. And I know a host of SHHH members who would be delighted to take on this role. Or, another approach that can be implemented immediately would be to demonstrate FM systems as part of an organized hearing aid orientation program (Ross l997).
In recent years, I’ve just about given up my old body pack FM receiver and transmitter (with lapel microphone) in favor of an FM boot and the hand-held FM microphone/transmitter. At various times, I’ve labeled the microphone/transmitter my “third ear” or “remote ear” and commented facetiously that I was hearing “trinaurally.” Actually, I think all of these descriptive labels have merit. By its nature, the FM microphone is a remote microphone, a third ear if you will. Since it supplements what I receive through my two hearing aids, I term it my “trinaural” condition. The FM capability and portability afford me the opportunity to locate a microphone closer to the source of sound, which is the key advantage of the device. Insofar as hearing-impaired people are concerned, this is a powerful step that they can take to help themselves. It literally puts the power to improve their own communicative situation into their hands. When the issue is framed this way, many hard of hearing people will respond positively to the use of a personal FM system, overcoming their initial cosmetic objections.
Most hearing aid users, including those with excellent hearing aids, can enumerate at least some communicative situations that give them particular difficulty. Here are just a few (there are many more) in which a personal FM system can provide significant assistance (Ross and Yuzon l994):
- Dinner with one person in a noisy restaurant. This may be the easiest situation in which to demonstrate the efficacy of a personal FM system. My wife tells me that when we are in this situation and I don’t bring my FM system, she has to lean over the table when talking to me and make an extra effort to be understood throughout the meal. When I pin my FM on her, she leans back, talks normally, and enjoys the dinner. (And if it’s a particularly noisy restaurant, then she has difficulty understanding me!)
- Having dinner with one other couple. Here, I locate the microphone between them and turn the hearing aid closest to my wife to the M/FM position. I pick her up with the HA microphone and the other couple through the FM. This is not ideal, since the FM microphone is placed on the table perhaps 18 inches from the other couple, but it is better than the alternative (four or more feet away from the hearing aid microphones).
- In a moving vehicle. If it is just my wife and me in the car, and it is a long trip and I am driving, I give her the microphone and keep my eyes on the road, rather than her face. Much more relaxing all around. If there is another couple in the car, then I locate the microphone close to the other couple, using the M/FM switch on the hearing aid closest to my wife. Thus I can pick her up through the HA mike and the other couple through the FM. A compromise, and far from ideal, but still much better than the hearing aids alone.
- At a noisy cocktail party or reception. This is a classic example of when a remote microphone can be valuable. In such situations, there is lots of noise, lots of people milling about, and lots of them to try to talk to. I simply place the FM microphone as close to the other person’s lips as possible. Although this works very well, there is a practical problem with the length and power of my arm. It is not convenient or easy to keep one’s arms extended for lengthy periods of time! Nor are some people comfortable with a microphone stuck under these chins. Sometimes, I’m asked if I’m recording the conversation!
- As a TV listening device while traveling. At home, I can use a number of systems in order to hear the TV better. But hotels, at least none that I’ve stayed in, ever provide a TV listening device. What I do is place the microphone/transmitter next to the TV speaker and receive the signal in a chair some feet away. I know that it improves my understanding and enjoyment of TV tremendously. (It is also a “marital aid”, since my wife can sleep or read in the room while I’m watching TV).
Many other examples can be given, but these should get the point across. FM systems work because the microphone can be placed closer to the source of sound than is possible with a personal hearing aid. And that’s all there is to it. But users have to take this step for and by themselves. It won’t be done for them. They have to be fully aware of the potential benefits that improved microphone placement will offer them, and be sufficiently assertive to openly and publicly employ the microphone. Not everybody can do this, but the rewards are there, and each time someone does it gets just a bit easier the next time.
From the humble beginnings I reviewed above, to the scope of papers included in this program, it is apparent that FM systems have made enormous progress in the intervening years. It would be presumptuous of me to comment on the technical aspects of these developments. Every one of the authors at this conference would know a great deal more than I do about the topics they cover. But I can comment on the human dimensions. These haven’t changed, since people’s hearing needs haven’t changed.
Hearing is still a priceless gift. The ability to communicate and to communicate effectively goes to the heart of what we are as human beings. Hearing shapes our lives from the moment of our birth until our death. It is through hearing that 99% of us learn language and it is basically through hearing that we receive our initial education. How we do both depends in large part on the quality of auditory signals that underlay language development and education. We know that for hearing-impaired children an appropriate sound enhancement system is crucial for these purposes (again, the 99% - as professionals we know that the other 1% also deserve our best efforts, but in other ways).
As we get older our hearing needs change but the ability to engage in effective verbal interchanges remains as a permanent necessity in our lives. And when these are less than perfect, when we continually miss part or all of some verbalizations, it can’t help but have some kind of impact on us, on what we are and how we think about ourselves. We know about the isolation, the withdrawal, the stress and anxiety caused by a hearing loss. We know how much poorer people’s lives become when they are denied full access to the social and cultural offerings of our society. And we know about the many people who just don’t go out, who don’t want to go to large dinner parties, receptions and the like. For adults, a personal FM system can help improve communication access in many of these situations.
So we’ve come a long way and it is really heartening to see the progress that has been made. But we shouldn’t be satisfied with our current status. There’s always a need for better technology, for new ideas to be implemented. So before closing, I’d like to offer my personal suggestion to our technical colleagues. I use a personal FM system in many group situations, but it is not as effective as I’d like it to be. What I’d really like is an integrated microphone/transmitter, no bigger than a ball point pen, that I can point at a speaker eight or ten feet away and pick up his/her voice clearly while suppressing the signals arriving from every other source. This would provide the best possible S/N in many communicative situations. Maybe by the time the second international conference on FM amplification is held, we’ll see examples of this new device. We would indeed be “Achieving Clear Communication Employing Sound Solutions,” to quote from the “ACCESS” program booklet.
Crandall, C. C. , Smaldino, J. J., & Flexer, C. (2004). Sound-Field Amplification: Theory and Practical Applications, Singular Publishing Group: San Diego, CA.
Flexer, C. (2003) Personal Communication
Myers, D. (2002) The coming audiocoil revolution. The Hearing Review, 9(9), 28-31.
Parente, M. (2003) Personal Communication.
Pimentel, R. (2003) Personal Communication.
Ross, M. & Giolas, T.G. (l971). Effects of three classroom listening conditions on speech intelligibility. American Annals of the Deaf, 116, 580-584.
Ross, M. (1972). Classroom Acoustics and Speech Intelligibility. In Handbook of Clinical Audiology, Katz, J. (Ed.) Williams and Wilkins: Baltimore, MD
Ross, M., Giolas, T.G., & Carver, P. (l973). The effect of classroom listening conditions upon speech intelligibility: A replication in part. Language, Speech and Hearing Services in Schools, 4, 72-76.
Ross, M. (1992). Room Acoustics and Speech Perception. In, FM Auditory Training Systems: Characteristics, Selection and Use, Ross, M. (Ed). York Press: Timonium, D
Ross, M. & Yuzon, E. (l994). FM systems for adults: Some ideas for realizing their full potential. The Hearing Journal, 47(2), 35-40.
Ross. M. (l996). Amplification for Children: The Process Begins. In Amplification for Children with Auditory Deficits, Bess. F, Gravel, J.S, & Tharpe, A. M. (Eds.). Bill Wilkerson Center Press: Nashville, TN
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Ross, M. (2001). Definitions and Descriptions. In Our Forgotten Children: Hard of hearing pupils in the schools. Davis, J. (Ed.) SHHH Publications: Bethesda, MD
Ross, M. (2002). Telecoils: The powerful assistive listening device. The Hearing Review, 9(9), 22-27.
Sarff, L., Ray, H., & Bagwell, C. (l981). Why not amplification in every classroom? Hearing Aid Journal, 34(12) 11.