Highlights from ISMA 2017

Socializing and general posts on wide-ranging topics. Remember, it's Poststructural!
Post Reply
Tunborough
Posts: 1419
Joined: Sun Dec 05, 2010 2:59 pm
antispam: No
Please enter the next number in sequence: 10
Location: Southwestern Ontario

Highlights from ISMA 2017

Post by Tunborough »

The 2017 International Symposium on Musical Acoustics wrapped up today in Montreal. Lots of good stuff about wind instruments on Monday, some of which may be of interest to the flute, whistle and pipe communities of C&F. For example ...

Henri Boutin, Sandie Le Conte, Jean-Loïc Le Carrou and Benoit Fabre, How Do Wood Polishing and Oiling Affect Acoustic Dissipation in the Bore of Wind Instruments?

The researchers asked recorder maker Philippe Bolton to make them tubes of maple, pear, boxwood and ABW, all cut with the grain, plus another of maple cut at an angle to the grain. They measured the rate of attenuation of sound in each tube at frequencies up to 2500 Hz, first in the raw tubes, then after the bore was polished, then after the bore was oiled and dried according to Bolton's recommendations.

The attenuation in the raw tubes depended significantly on wood species: inclined maple tube >> maple > boxwood > pear. Even before polishing, the ABW tube attenuation was only slightly more than would be expected from an ideal pipe.

After polishing, the attenuation in the maple, boxwood and pear was lower and much closer together, although they still ranked in the same order and not quite ideal. The inclined maple tube had improved, but was still worse than the other tubes had been before polishing.

After they were oiled and dried, all four with-the-grain tubes had essentially ideal attenuation. The inclined maple tube had improved greatly, but still attenuated more than an ideal pipe above about 500 Hz.
Tunborough
Posts: 1419
Joined: Sun Dec 05, 2010 2:59 pm
antispam: No
Please enter the next number in sequence: 10
Location: Southwestern Ontario

Re: Highlights from ISMA 2017

Post by Tunborough »

Alexis Guilloteau, Philippe Guillemain and Michael Jousserand, Beneficial Aspects of Toneholes Undercutting Applied to Clarinet Design.

When toneholes were undercut rather than being left cylindrical on a clarinet-like instrument, Guilloteau found that players could keep the instrument in tune better over the full range of dynamics, and that notes would start playing at lower pressures (oscillation threshold) and continue playing at higher pressures (extinction threshold).
Tunborough
Posts: 1419
Joined: Sun Dec 05, 2010 2:59 pm
antispam: No
Please enter the next number in sequence: 10
Location: Southwestern Ontario

Re: Highlights from ISMA 2017

Post by Tunborough »

Cassandre Balosso-Bardin, Augustin Ernoult, Patricio de La Cuadra, Ilya Franciosi and Benoit Fabre, Music or Mechanics? Understanding the Role of a Bagpiper’s Arm.

In a study involving novice and expert players of Galacian bagpipes (gaita) and Mallorcan bagpipes (xeremies), the researchers found that experts were much better at keeping the chanter and drones in tune, thanks to better control of their bag arm. An opinion survey indicated this was an important, if not the most important, skill distinguishing experts from novices.
Driftwood
Posts: 145
Joined: Sun Mar 13, 2011 7:24 am
antispam: No
Please enter the next number in sequence: 12

Re: Highlights from ISMA 2017

Post by Driftwood »

I was interested to read your summaries of the research papers, Tunborough, especially the one involving an inclined bore. I've made an extremely inclined bore chanter and posted some details on the Chiff Uilleann a while back. It has a serpentine bore, so there are lots of inclinations and it was made from some scrap mahogany. To seal it I used several coats of shellac and finished off with a few coats of thin picture varnish before final assembly. I imagine the shine will deteriorate over time and restoring it would probably be very difficult or not practical. I've often wondered if it would be worth the effort of making a similar chanter using a really close-grained hardwood that could be subsequently polished or oiled, if needed, without a build-up of residue from surplus oil at various points along the very bendy bore.
Post Reply