What is meant by indirect control? It means, in short, the automatic
response of the mechanism to the idea. By way of illustration. If I
should ask my pupil to make her vocal cords vibrate at the rate of 435
times per second she could not do it because she would have no mental
concept of how it should sound: but if I strike the A above middle C and
ask her to sing it her vocal cords respond automatically at that rate of
vibration. It is the concept of pitch which forms the vocal instrument,
gives it the exact amount of tension necessary to vibrate at the rate of
the pitch desired, but the action is automatic, not the result of direct
effort.
It may be said that in artistic singing everything is working
automatically. There can be no such thing as artistic singing until
everything involved is responding automatically to the mental demands of
the singer.
Mention has been made of the automatic response of the vocal cords to
the thought of pitch. That part of the mechanism which is so largely
responsible for tone quality, the pharynx and mouth, must respond in the
same way. This it will do unerringly if it is free from tension. But if
the throat is full of rigidity, as is so often the condition, it cannot
respond; consequently the quality is imperfect and the tone is throaty.
The vocal cavity must vibrate in sympathy with the pitch in order to
create pure resonance. It can do this only when it is free and is
responding automatically to the concept of tone quality. To form the
mouth and throat by direct effort and expect a good tone to result
thereby, is an action not only certain of failure but exceedingly
stupid.