6. ACOUSTICAL ANALYSIS OF THE PEDAL IN LISZT'S WORKS
6.6 The effect of pedal release on the envelope
!
6.6 THE EFFECT OF PEDAL RELEASE ON THE ENVELOPE !
!
In the present section I deal with pedal effects written by Liszt that are produced by releasing the pedal. In Chapter 3.5 I presented four examples of this kind of pedal effect. For further analysis I have chosen an example (6.3) from the work Aux cyprès de la Villa d’Este (Thrénodie I) in Années de pèlerinage III. In the other three examples (3.10-3.12) of Chapter 3.5 the releasing of the pedal occurs at the moment when some pianos keys are to be depressed. In this situation it would be practically impossible to distinguish between the effects of pedal release and key depression on the envelope. "!
In the first two bars of Example 6.3, three chords in C major in different registers are to be played rather loudly under depressed pedal. When the third chord (in a relatively high register) has sounded for a while, the pedal is to be released to break the sounding of the first two chords. The tones of the third chord are to be held by fingers. The dampening of all strings below the tone e1 causes a sudden drop in loudness. In general, this kind of dynamic contrast is not exceptional in music; neither does it produce any blurred sound in this example. However, as we have seen in Chapter 3.5, the intention of the composer in Bar 202 of Example 6.3 was not a sudden drop in loudness. In Chapter 5.2 it was mentioned that the loudness of bass tones decreases at a lower rate than that of treble tones. As the chords whose sounds are broken by pedal release are located in the low register the contrast in the dynamics is therefore sharper in this example. !!
!
Example 6.3 Bars 201-205 of Aux cyprès de la Villa d’Este, Thrénodie I (Années de pèlerinage III). "
! !
Before we go on to study the effect of pedal release on loudness as played on different instruments in Example 6.3, we have to return to the differences in the envelopes of a single tone (Part 5). Based on the analysis of a single tone (Chapter 5.2), loudness decreases faster on the Chickering than on a modern piano in every register. It is therefore logical that in Bars 201-202 of Aux cyprès de la Villa d’Este the decrease in the loudness of the chords up to the moment of pedal release is also different on the two pianos. On a historical piano the drop in loudness before the pedal release indication is big enough for the contrast in loudness before and after pedal release to be quite insignificant. "
!
Figure 6.3 shows the envelopes of Example 6.3 played on the two different pianos. The first bigger peak represents the lowest chord, the second peak the next chord in the middle register and the third one the chord in the treble register. The loudness reduction rate for all the chords on different pianos is equivalent to the envelopes of the single tones presented in Chapter 5.2. It appears from a comparison of the envelopes from the third chord to pedal release that the loudness on the Steinway decreased at a more even rate, whereas on the Chickering it dropped quite abruptly. The moment of pedal release is more apparent on the Chickering (Figure 6.3a) than on the Steinway. In Figure 6.3a we can even see a small, almost imperceptible peak (wave) between the last two stronger peaks. This could not be produced by the damping of the strings. Hence, this small peak in the envelope was most probably produced by some mechanical noise in the pedalling. On the Steinway, the pedal release occurred the moment the small saw teeth-likewaves end (in the envelope). Although the pedal release on the modern piano produced a greater drop in loudness, it is hardly detectable in Figure 6.3b. "
"
Figure 6.3 The envelope of Bars 201, 202 and the first chord of Bar 203 from the work Aux cyprès de la Villa d’Este played on a) the Chickering, b) the Steinway. "
! !
A visual comparison of Figures 6.3a and 6.3b at the moment of pedal release in this example is complicated. The pedal release can be observed approximately halfway between the last two peaks. Its visual effect in the envelope fails to accurately reflect its acoustic effect in this example. In Chapter 5.2 some of the properties of the piano envelope have been described. After a relatively strong attack transient, the loudness of a piano starts to decrease, and the decrease rate depends on the frequency. When the amplitude level has dropped to about 35% of the maximum (at the attack transient) the dropping rate decelerates and loudness continues to decrease at a less noticeable pace. In Aux cyprès de la Villa d’Este the distance in time between pedal release and each chord in Bars 201-202 is, at least on the Chickering, long enough for the loudness level to drop to 35% of the maximum. Thus, at the moment the dampers fall on the strings the loudness level is already rather low, and the pedal release does not result in a significant drop in loudness. The reason the release of the dampers cannot be detected from the graphics of the envelope as clearly as by auditory sensation is probably that the envelope shows the amplitude of the strongest
vibrating frequency. When the vibration of the selected strings was suddenly damped, the envelope still showed the vibration amplitudes of the strings that were not damped. Thus, if the range of vibrating frequencies becomes narrower the listener perceives it as a decrease in loudness. In Aux cyprès de la Villa d’Este this means that raising the pedal cuts off all frequencies lower than 330 Hz (e1). "