At first, lowering the pitch of a string increases overtone content slightly, then, as scordatura becomes more extreme, the sound becomes overtone-weak. The timbral effect of changing contact point is reduced.
For very low tunings, particularly under high excitation force, the string often rattles against the fingerboard. This ratting and the noise-based sounds are particularly evident for the bowed string. The lower strings are more quickly affected by scordatura.
The C string is tuned a fifth lower. The string rattles slightly against the fingerboard and the pitch is unstable.
The C string is tuned an octave lower. The string rattles against the fingerboard, especially when the string is stopped, and the pitch is unstable.
Scordatura tunings above ‘normal’ are less flexible. If the string is tuned more than a tone higher, it is likely to break. Slight increases in pitch by scordatura increase the loudness of a tone and weaken the upper partial content. It is less easy to excite the string close to the bridge and the string is less easy to set into motion, making fast tones and articulated tones more difficult.
▶︎A NOTE ON BOWING
In the case of the bowed string, initially the string is more easily set into motion by the bow, i.e., the minimal bow force is lower, but as the detuning increases, vibration becomes increasingly difficult to sustain. The sound becomes noisy and scraping. The pitch of the vibrating string often fluctuates: the pitch gets sharper as bow speed increases and lower as bow pressure increases. Eventually the pitch of the tone is obscured by the noise element of the sound, which is reduced to a ‘fluttering’ timbre.
Scordatura creates a technical difficulty for cellists that is not always recognised. The distance between string and fingerboard and the tension of the string are different. Therefore, the sensation of stopping the string with the finger is unfamiliar. The string’s reaction to the bow is also different; fundamental technical habits have to be adjusted in order to control intonation and sound.