Close Encounters

On the 1st of  October a meeting was convened at the Bionic ear Institute in Melbourne between four CI (cochlear implant) recipients, four composers involved in the Interior Design project and 2 scientists. The meeting was semi-formal and served to facilitate communication between implant recipients and composers as well as the filming for a slot on ABC TV’s Art Nation program (to be screened Sunday 31 October). It was an incredible experience for a number of reasons to be outlined below.

To be brutally honest, I had been becoming gradually a little pessimistic about the prospect of being able to successfully compose music for appreciation via the cochlear implant hardware. All of the research on pitch perception and audible stream segregation seemed to be painting a pretty bleak picture in terms of being able to convey a musically pleasing experience to a listener wearing the device. In my capacity as an experimental sound artist, creating a ‘musically pleasing’ experience is rarely at the forefront of my thinking when I’m composing works, but given the nature of this particular project and having heard first hand how much these implant wearers miss music, the weight of responsibility had begun to bear down! In the end, meeting some recipients, talking with them and experiencing sound with them, hearing their repsonses and hearing their stories, was great way to re-energize my ailing optimism.

So many interesting things were raised during the meeting that it’s difficult to know where to start. One of the recipients, for example, reported listening to music that he would never have considered listening to before. A long-standing lover of classical music, he found himself enjoying listening to R’n’B! He reported being drawn in by the emphasis on rhythmic impulsion  and the clear lyrics. What was interesting was that he found attempts to listen to classical music frustrating, as the gap between what he knew should be happening and what was actually happening was quite wide. The more familiar he was with the work, the more frustrating the experience of trying to listen to it. So new music is firmly back on the agenda!!

I had asked some of the other composers to bring along some sounds to the meeting (either acoustic or electronic) to play to the CI wearers to get some real-time feedback on some of the ideas the composers had been working with. I’d like to thank Eugene Ughetti (of speak percussion) particularly for the fervour and forward thinking that he brought to the meeting. Eugene arrived replete with a large Tam Tam (which is a big gong for those not familiar with the lingo), a set of smaller gongs of various sizes and some skinned drums and cymbals. He had devised a whole series of listening experiments designed to ascertain the thresholds for perceiving difference (in both pitch and rhythm) afforded by the implant hardware. I’m not going to go into an exhaustive description of all of the experiments but I will describe in some detail the Tam Tam test as the results were most encouraging.

When a Tam Tam is struck gently with a soft mallet, the tone produced is a sonorous low tone, the frequency of which is determined by the fundamental frequency of the Tam Tam itself. Repeated soft strokes will produce a continuous low tone and quite a pure tone, akin to a low sine wave. As the pressure of the strokes increases, upper partials begin to emerge above the fundamental. More harmonics are activated with increased pressure, gradually opening up the harmonic spectrum until what was once a pure tone has been transformed into a complex sound. Because this progression comes out of the activation of one material (the Tam Tam), the transition seems quite smooth and somehow logical. What Eugene wanted to ascertain was whether the CI recipients would hear this change in tone as a continuous one coming from one instrument, or whether they would percieve the change in sound as a change in instrument i.e. coming from some completely different source. Two interesting observations could be made during the discussion after the sound had been played and experienced. Firstly, it was interesting to observe first hand the loudness limitations of the implants. The CI wearers couldn’t hear the gong unti lit reached a certain volume. Noting this fact triggered a useful discussion on around the idea of ‘loudness’ and what that might mean whn composing for the cochlear implant. The implant software employs limiting strategies to ensure that current levels in the electrodes don’t cause pain for the wearer. This can result, obviously, in a rather unnatural appreciation of relative loudness levels in the environment. Given that shifts in volume are fundamental to musical expression, Eugene was fishing for the limits in order to structure his thinking more effectively, in essence, to internalise the relative dynamic behaviour of the implant for compositional purposes. It was enlightening for all of the composers present. Secondly, of great interest was the response of recipients to the change in sound quality across the duration of the demonstration. Most of the recipients reported feeling that there was ‘another’ sound that began to happen over the top of the original sound. Which is what Eugene was predicting. Perhaps more heartening though was that all of the recipients reported that the sound was really pleasing to listen to. Some even used the word ‘beautiful.’ This really piqued the interest of the scientists who have had a lot of experience playing musical sounds to CI wearers and who reportedly rarely have a subject report a pleasing listening experience.

The sound transformation in the Tam Tam was also a wonderful listening experience for all in the room without implants! Some of the descriptions of the listening experience offered by the implant wearers seemed to gel quite closely with the experiences of others in the room as well. It felt like we had just shared a musical moment, or at least a moment in musical sound. Given that this mode of sharing is largely what this project is all about, it felt like a great breakthrough. It certainly served to annul my previously mounting pessimism.

Lots more happened! But my battery is about to die. More soon.

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