PROCEEDINGS 
OF THE 
Cambridge Whilosophical Society. 
~ Lhe Origin of the ‘ Wolf-note’ in Bowed Stringed Instruments. 
By G. W. Waite (M.Sce., 1851 Exhibition Scholar), Fitzwilliam 
Hall. (Communicated by Professor Sir J. J. Thomson.) 
(Plates II—IIL.) 
[Read 8 February 1915.] 
| On all stringed instruments of the violin type a certain pitch 
ean be found which it is difficult and often impossible to produce 
by bowing. This note is called the ‘wolf-note’ and usually occurs 
at an interval of an eleventh or twelfth above the lowest note of 
the instrument. At this pitch on either string the bow refuses to 
“bite, and a soft pure tone is almost impossible to obtain; if the 
pressure of the bow on the string is increased the tone resulting 
is usually of an unsteady nature with considerable fluctuations in 
‘Intensity (the note probably received its name from this phe- 
-homenon). It was thought that possibly an analysis of the vibration 
of the belly of the instrument for frequencies in the neighbourhood 
of the ‘ wolf-note’ would settle the question of its origin, on which 
there is considerable disagreement amongst musicians. The 
Instrument selected for experiment was the ’cello. On such 
instruments the imperfect note is usually very pronounced 
especially when played high up on the G-string. 
The vibration of any part of the body of the instrument was 
recorded as a line on a moving photographic plate by reflecting a 
beam of light from an optical lever one leg of which rested on the 
vibrating surface. Fig. 1 shows the method of holding the ’cello. 
A rigid wooden framework was clamped tightly to a table. The 
framework served to hold a steel rod in such a position that it 
stood parallel to and at the same height as the neck of the 
instrument when standing vertically with its peg on the table. 
lA 
VOL. XVIII. PT. III, ( 
