Dies ist ein Titel H3

Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Quisque sed felis. Aliquam sit amet felis. Mauris semper, velit semper laoreet dictum, quam diam dictum urna, nec placerat elit nisl in quam. Etiam augue pede, molestie eget, rhoncus at, convallis ut, eros.

The string

String tension

pulling the string

It is possible to increase string tension by pulling the string across the fingerboard with the stopping fingers.  The pitch becomes slightly sharper and then falls to its normal pitch as the string is released.  Wider pitch variations are possible on lower strings

Video 43

Pitch bends by pulling the string.  At first a string is pulled and released during vibration.  Then, a string is pulled during vibration and released when vibration has finished.  Finally, a string is pulled before excitation and released during vibration.  The pitch bends are shown for the plucked, struck and bowed string and for bowed harmonics.

Hints tips and extra bits

A ‘cracking’ sound can sometimes be heard as the string moves across the fingerboard.  This is the sound of the metal string against the fingerboard.

pushing between bridge and tailpiece

Pushing down (towards the cello body) upon the string between the bridge and the tailpiece also makes a pitch bend.  The action can be done with the right hand immediately after excitation or, for an open string, with the left hand, in which case the timing is more flexible.  Fast repetition of the action produces a vibrato effect.

In context

Pushing the strings between bridge and tailpiece can leave the string slightly detuned, making it sharper. 

Video 44

Pitch bends by pushing the string between bridge and tailpiece.  An open string is pushed during vibration, then pushed during vibration and released after vibration, then pushed before excitation and released during vibration.  Then, a vibrato effect is produced by repeatedly pushing during vibration.  The pitch bends are shown for the plucked, struck and bowed string.

Video 45

Pitch bends by pushing the string between bridge and tailpiece.  A stopped string is pushed during vibration, then pushed during vibration and released after vibration.  Then, a vibrato effect is produced by repeatedly pushing during vibration.  The pitch bends are shown for the plucked, struck and bowed string.  

Hints, tips and extra bits

Pushing the string between bridge and tailpiece often detunes the string (making it sharper), especially if it is pushed for a long time or particularly hard.  

scordatura

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. 

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.  

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. 

 

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.

In context

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. 

 

 

acoustical information

Summary

 

If the tension of the strings is changed by scordatura, the outcome depends on the extent of the detuning.  Slight decreases in tension increase overtone content since, relative to the new lower fundamental, the frequency of the highest possible overtone increases.  However, if the tension is decreased further, overtone content is restricted by the slackness of the string, encouraging damping.  Eventually, the string becomes difficult to control and responds slowly to excitation, especially bowed articulation.  Increases in tension by scordatura are limited because the string is liable to break under high tension.  However, slight increases in tension have the effect of detuning the upper partials and making the string less responsive to excitation, particularly bowed articulation. 

acoustical information

Detail

 

As a string is tuned down, its tension decreases.  Small decreases in tension might at first strengthen the overtone content slightly since the frequency of the highest contributing overtone, set by string width and other factors, stays constant for a decrease in fundamental pitch.  However, further decreases in tension weaken the potential overtone content of the string; the less tense string is shaped less sharply at the bridge and nut and more energy is lost to damping as vibration is reflected in these regions.  Therefore, for a fixed contact point, the timbre is less overtone-rich and the scope of sul ponticello sound is reduced.  For small decreases in tension by scordatura, the string is easier to set into motion.  Therefore a relatively ‘normal’ sounding tones is possible under low excitation forces, flautando and overtone-takeover effects are more difficult to produce.  As tension becomes very low, the vibration of the string is made up of much torsional movement, causing the string to respond slowly to excitation.  This causes some irregular pitch changes and a noise component in the sound.  The scope for varying plucking/striking force and bow speed/pressure is reduced, particularly at the upper end of the scale, and loud sounds are unsustainable.  For high excitation forces the string often strikes the fingerboard during vibration.  Eventually the string becomes too ‘floppy’ to sustain transverse vibration.  The lower strings are first to be effected by torsion since their increased width increases the propensity to vibrate in such a way.

 

As tension increases above ‘normal’ tuning, the sound becomes slightly louder since the string exerts an increased force on the bridge; the coupling between bridge and body is strong.  Higher partials become weak and out of tune with the fundamental due to string stiffness.  Vibration becomes difficult to control, particularly in bowed sound.  Rapid bow changes are difficult as the string is very sensitive to changes in plucking/striking force and bow speed/pressure.  Longitudinal vibration of the string might be heard in the form of high-pitched squeaks.

 

If the tension of one string increases or decreases significantly, the corresponding change in down bearing force on the bridge affects the amplitude of the other strings.  The amplitude of the other strings increases and decreases in inverse proportion to tension.

Video 46A

The C string is tuned a fifth lower.  The string rattles slightly against the fingerboard and the pitch is unstable.

Video 46B

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.