This Monday we had the second round of meetings between the group of composers working on the “INTERIOR DESIGN” project and a group of cochlear implant recipients who are “road-testing” musical material.
The aim of these meetings is basically to help the composers establish a musical palette they can use in their compositions. One of the things we know for certain is that the standard “palette” of sounds used in most music today doesn’t translate well through a cochlear implant. Harmonies constructed using the standard 12-note scale, for instance, cannot be relied upon to produce the same perception of major and minor tonality that someone with normal hearing experiences.
One of the main points of discussion was again loudness and dynamic range. As the perception of musical pitch is not well understood in cochlear implant recipients, it’s likely that the composers will be using other cues, such as loudness and timbrel changes, heavily in their works. There was thus alot of discussion about how best to ensure that quiet sounds sound quiet, and loud sounds sound loud.
We set up three seperate sound booths, and played a game of musical chairs, with each CI listener going into each sound booth to hear and report on what they heard. James Rushford brought his viola, and was experimenting with how various combinations of pitch and timbre were perceived. By preparing strings with small dots of bluetack, the higher harmonics were reduced, and this seemed to increase the ability of the listener to distinguish between closely-spaced pitches.
Ben Harper, who’s also writing about his experiences in the project on his blog here, has developed a new tuning system based on the 22 channels in a standard cochlear implant sound processor. Most of the CI listeners we had in on Monday seemed to really like this tuning system, reporting that it sounded harmonious or pleasant.
Natasha Anderson and Rohan Drape were in the last booth. Natasha brought in her laptop and pro tools setup, and played back a variety of sampled and synthesised sounds. These ranged from spacey echo-ey sounds, to strong rhythmic beats and quite raucous noise. This variety sparked off a “what is music” type discussion – a pretty fascinating development which we weren’t expecting. It’s a good sign – we’re hoping that CI users, musicians, and normal-hearing music lovers can start to have a dialogue – these kinds of discussions show that at some level, musical communication is it least occurring! Rohan had prepared some visual diagrams to go along with a score – I think this is also an interesting approach, and something that we’re testing in the lab as well!
More reports as it comes!