Development of Helmholtz motion and related wave patterns in the bowed string
2001 (English)Licentiate thesis, comprehensive summary (Other scientific)
Of the many wave patterns that the bowed string is capableof producing, the so-calledHelmholtz motion(Helmholtz 1862) gives the fullest sound in terms of power andovertone richness. Papers one and two of this thesis deal withthe creation of this particular string movement: The firstpaper, based on computer analysis, describes some systemparametersinfluence on the transient in terms ofplayability. The second paper deals with theperception of real violin attacks of different transientqualities. Not surprisingly, it can be shown that tone onsetsare considered superior when the attack noise has a verylimited duration. However, the character of the noise plays animportant part too, as the listeners tolerance of noisein terms of duration is almost twice as great forslipping noiseas forcreaksorraucousnessduring the tone onsets. The third paperdescribes the triggering mechanics of a peculiar toneproduction referred to asAnomalous Low Frequencies(ALF). If properly skilled, a player can achieve pitches belowthe normal range of the instrument. This phenomenon, analysedand explained through use of computer simulations, is relatedto triggering waves takingan extra turnon thestring before causing the strings release from thebow-hair grip. Since both transverse and torsional propagationspeeds are involved, two different sets ofsub-rangednotes can be produced this way.
Place, publisher, year, edition, pages
Institutionen för talöverföring och musikakustik , 2001. , 13 p.
IdentifiersURN: urn:nbn:se:kth:diva-1283ISBN: 91-7283-080-8OAI: oai:DiVA.org:kth-1283DiVA: diva2:7098
NR 201408052001-08-202001-08-20Bibliographically approved