Historically Informed Performance
Damping Methods
The amplitude of sound will diminish over time due to resistance. The decay of amplitude over time is called damping. For timpani, there are five possible reasons for energy loss resulting in the damping of the sound emitted from the instrument. 47 48 50
1) radiation of sound
2) mechanical loss in the membrane
3) viscothermal loss in the confined air [inside of the bowl]
4) mechanical loss in the kettle [bowl] walls
5) mechanical loss in the frame and external parts
For generating a shorter sound envelope, we will focus on number two from above; 2) mechanical loss in the membrane. The information below can be used as a starting point for emulating various types of period timpani sounds via damping using gel-dampers e.g., Moongel Damper Pads while employing modern instruments with Mylartm heads. The author prefers to use different sizes of circular gel-disc mutes placed directly in the center of the head to further reduce the energy of mode 0,1 and the subsequent inharmonic concentric modes. The concentric modes do not contribute to the pitch of the instrument, but they do contribute to the volume, resonance and sustain of the instrument. For the science behind how timpani heads vibrate to produce pitch, please see the sections Vibrating Circular Membranes, Membrane Modes, and Preferred Modes.
Method I
Place the pitches on the higher two drums e.g. 26″ & 23/24″ and place a gel-damper or some type of mutes in the direct center of the heads. You need to have very clear heads if you still want a pitch component to your sound. The lower range gives the drums a “slack” sound without a lot of high overtones. The damping diminishes a lot of the sustain and produces more of a dry sound (if your heads are clear), yet there is still plenty of pitch to the sound. If a sound comprised of percussive attack transients and drum color only is desired, i.e. a lack of a focused pitch, the drums can be slightly de-tuned at each lug point. It may seem counter-intuitive to de-tune timpani, but a dry, slack and percussive sound without a lot of pitch was purported to be the characteristic sound of very early timpani. A slightly “out-of-tune” head will also create more mechanical loss in the membrane.
Method II
Place the pitches on your center drums (29″ & 26″) and place a gel-damper or some type of damper in the direct center of the head along with suede mutes or split a gel-damper and place it on the edges slightly muting the head right where it touches the bearing edge. Experiment with placement of the side dampers and various lighter weights of hard sticks. Creating and damping via a pseudo backbone on Mylartm works well (see below).
Method III
Place the pitches on the lower drums (32″-29″) and damp in a similar fashion as #2. The higher range on the low drums will give you a little bit less ring and bit drier sound. Again, experiment with placement of a gel-damper or mutes of your choice, and various weights of hard sticks. Using larger drums (damped) works well for larger ensembles when you want to emulate the effect of the early English “Double Drums” or when playing with a large brass compliment where you need volume, but not a lot of sustain to your sound.
The author uses different sizes of clear, circular gel-disc mutes made from basically the same material as Moongel Damper Pads, which he use regularly in the dead-center of the head. The gel-discs are slightly thicker than the Moongel Damper Pads. The circular shape better conforms to the shape of the higher concentric modes and damps the overtones created by these modes (without sacrificing pitch) better than the rectangle shape of the Moongels. This method removes more of the unwanted non-harmonic concentric modes, while leaving the pitch producing preferred modes intact. The sound is considerably drier, and less resonant.
It is extremely important to have different sizes of circular gel-disc mutes to reflect the sizes of the drums, and different acoustical environments. Too large of a gel on a smaller drum may make the drum sound dull, while too small a gel on a large drum may have little noticeable effect. Experimentation is often needed to find the right combination for the acoustics of the room and the size of the ensemble.
Pseudo Backbone
Damping Mylartm Heads with Moongel Damper Pads
When using both split and large Moongel Damper Pads, place them on the drums so that they bisect the drum creating a pseudo backbone placement allowing you to create a playing spot on either the shoulder/hip area or the belly.
Pseudo Backbone II (belly)
Creating a pseudo backbone and playing on the belly of the backbone plane projects the pitch of the principal tone yet limits some of the higher overtones and slightly cuts down the resonance and sustain of the head. Good for Classical period sound.
Pseudo Backbone III (shoulder/hip)
Creating a pseudo backbone and playing on the shoulder/hip of the backbone plane helps project the pitch of the principal tone yet limits some of the higher overtones and cuts down the resonance and sustain emulating an earlier period sound. Good for Baroque period sound.
Michael Baker, Principal Timpani/Percussion Halifax, Nova Scotia, uses tape on his drums as a method of damping. For example, below is Michael’s taping method to damp modern 26″ and 24″ Light Mark XIV timpani for a performance of Handel’s Messiah.
Some players prefer to use suede mutes for damping. For more information on how to make and use suede mutes, please visit How To Make Duff-Style Suede Timpani Mutes by Dwight Thomas.
One must remember that there is no consensus as to 1) the best way to damp a drum, 2) the best location to to place a damper, 3) the material to use as a damping device and 4) how much to damp a drum. Along with using different sizes of circular gels in the center of the drum to mitigate higher partials, the author also uses suede mutes at the edge of the drum to address resonance issues. The key is to always pay close attention to the acoustics of the room, the acoustics of the instruments you are playing, and the size of the ensemble and make your adjustments tastefully. Sometimes little or no adjustment is necessary, other times you will have to work harder at creating a HIP sound. Experimentation is usually necessary.