Seeing the Sounds That You Sing 



Clear pictures are made of the vibrations of your voice 

 so that 5'ou can detect by sight an error - in pitch 



IS it difficult 

 for you to 

 sing in tune? 

 Do you distrust 

 your ear? 

 Cheer up! there 

 is hope. You 

 can !'find' 

 yourself by 

 your eye. You 

 can stand be- 

 fore an instru- 

 ment and see 

 in clear pic- 

 tures every 

 pitch move- 

 ment of your 

 voice as 30 u 

 are singing; 

 you can see ex- 

 a c 1 1 >' how 

 many vibra- 

 tions per sec- 



The tonoscope in the psychological laboratory of the Univers- 

 ity of Iowa. It registers the pitch of the tone played or sung 



five dots so 

 placed that, 

 when acted 

 upon by a sen- 

 sitive light, 

 they arrange 

 themselves in 

 characteristic 

 figure forevery 

 possible pitch 

 within the 

 range of the 

 human voice. 

 Each figure 

 points to a 

 number which 

 indicates the 

 pitch. The 

 dots are ar- 

 ranged into 

 one hundred 

 and ten rows; 

 the first one 



ond your vocal organs are producing, and 

 you can thus tell, at the very moment of 

 singing a note, what error is involved. 



Moreover, the player of the violin, flute, 

 cornet, or other instrument, may treat his 

 instrument in the same way. A person 

 many hundreds of miles away may connect 

 "long distance" with this "musical eye" 

 and project the vibrations of his instrument 

 on the screen. There is, indeed, no limit 

 to which the musician may not go in 

 improving his playing. 



The instrument which will do all this is 

 the tonoscope. As yet, there is only one 

 tonoscope available, and that is in the 



has one hundred and ten dots, the next 

 one, one hundred and eleven dots, and so 

 on, each successive row having one more 

 dot than the preceding one, up to the 

 last, which has two hundred and nineteen. 

 When a musician is singing before the 

 instrument and sounds a tone, the row 

 which has the dot frequency that cor- 

 responds to the vibration frequency of the 

 tone will stand still, while all other dots 

 move and tend to blur. The row which 

 stands still, therefore, points to a number 

 on the scale which designates the pitch of 

 the tone. In other words, to see the pitch 

 of the tone, one has only to see the number 



psychological laboratory' of the University of the line that stands still. 



of Iowa. Professor Carl E. Seashore says: 

 "It furnishes us the first ready and at the 

 same time reliable and accurate means of 

 registering directly the pitch of a tone as 

 sung, spoken, or played with a musical 

 instrument in such form that it can be 

 operated with convenience and safety out- 

 side the technical laboratory." 



In brief, the instrument works on the 

 principle of motion-pictures. It converts 

 the sound vibrations into pictures on a 

 screen. The screen, which may be seen 

 through the opening in the front of the in- 

 strument, has eighty thousand and ninety- 



The tonoscope is operated by electric 

 current, which enables it to run indefinitely 

 without disturbance. The speed of the 

 revolving screen is controlled by a tuning- 

 fork with which it must keep step, being 

 driven by a synchronous motor. The 

 instrument indicates the actual pitch of. 

 any note to an accuracy of often less than 

 a hundredth of a tone. Even if a note as 

 constant as that of a tuning-fork is sounded, 

 the pitch is recorded accurately in tenths 

 of a vibration, because fractions of vibra- 

 tions may be read in terms of the number 

 of dots that pass per second. 



29 



