Beating the challenges of Timpani maintenance!
Of all the percussion instruments used in public school instrumental programs, timpani often present the most challenges when it comes to maintenance and repair. Timpani that function properly are essential to the intonation of bands and orchestras. Precise tuning of each instrument is critical to the success of the entire ensemble. Like piano, timpani repair is more efficiently performed on site rather than at a local music repair shop. Following are some modern tips regarding some old challenges.
First, begin by identifying the brand and model of timpani. Only a few brands and models existed before 1978. Today, the standard brands found in public schools include Adams (Pearl Corporation), Ludwig, Slingerland (now obsolete, but still in some schools), Majestic, Pearl, Premier, and Yamaha. The list of professional brands is considerable as well. Second, identify the “type” of timpani:
Regular collar – the plastic head bends over the timpani bowl at a 90 degree angle (older model timpani).
This type of instrument has a larger tuning range, but consequently a tighter and often less desirable tone.
Extended collar – the plastic head bends over the timpani bowl at about a 30 - 45 degree angle (most newer models of timpani are this style). The head extends about 1” past the circumference of the bowl.
This type of design has a smaller tuning range, but a superior tone.
Setting the correct pitch range. Timpani are manufactured with a desired pitch range for each instrument. The most common timpani sizes and ranges are listed below (normal letters = lowest note or highest note in range; bold letters in [ ] indicate normal “playing” or “usable” range):
Note: use the lowest pitch on the chart, which still allows for the full range in the brackets.
32” = C/C# [D – A] A#/B
29” = D#/E [F – C] C#/D
26” = G#/A [Bb – F] F#/G
23” C/C# [D – A] A#/Bb
Most timpani have a tension adjustment knob located just above the tuning pedal. This knob is intended to provide slight adjustment to the high tension spring that counter-balances the tension between the head and pedal. In most situations, this adjustment should be left in the factory position.
Head replacement. Replacing timpani heads has become more complicated over the past 20 years. The complication results from the number of timpani brands and models that have entered the marketplace, the regular collar vs. extended collar types, and the methods of sizing timpani heads (some brands measure in inches while others measure in centimeters). To avoid purchasing an incorrect head, many retailers suggest removing the old heads and bringing them in to a store to obtain an exact match. This method is not practical for every situation. The Steve Weiss Music Company has an online timpani head measuring article, as well as links to timpani head sizing charts for REMO and EVANS timpani heads (this is where the identification of your brand and model of timpani is useful): http://www.steveweissmusic.com/timpani_head_size
Teflon tape. Once the correct heads have been acquired, the timpani bowl edges can be prepared for the new heads. The edges should be cleaned with a fine steel wool to remove any debris or old head lubricants. In the past, bowl edges were often lubricated (to allow the heads to move over the edge more fluidly) with paraffin wax, or some type of non water-based lubricant like automobile door grease. Both methods eventually result in the collection of dust and debris under the timpani head. Today, professionals use Teflon tape. This tape, adhesive on one side, allows for the most efficient timpani head fluidity, without collecting debris. Note that the Teflon tape used for timpani is a unique design available from percussion retailers and not the thin white Teflon tape available from local hardware stores (used by plumbers to wrap pipe connections).
Replacing the heads. Once the Teflon tape has been applied to the edges of the bowls and the heads replaced, it is time to set the range of each drum. Using a strobe tuner to check pitch range, the tension rods may be slowly tightened (crisscrossing the head in small turns) until the pedal sits with the heel on the floor, and the timpani head is approximately in the lowest pitch range according to the chart above. On most school model timpani, the pedal will self-adjust as tension is applied to the head. The pedal will begin in the forward most position, with the heel moving toward the floor as the instrument reaches the manufacturer’s tuning range.
Clearing the heads. “Clearing” refers to the process of tuning the heads to the identical frequency at each tuning post. A mechanical device called a Drum Dial (available from most music retailers) can speed up this process a great deal. The Drum Dial measures the head pressure at the point of contact. The theory is that if the head pressure is equal at each tuning post, the frequency or pitch will be the same at each tuning post. Although the Drum Dial will speed up the process, nothing substitutes for using your ear to fine tune the area in front of each tuning post. Clearing the heads may drop or raise the lowest pitch of each instrument, so continue to work to clear each head until each drum works properly in the manufactured range.
Shimming the rims. Timpani that have been moved often, or have been damaged due to poor storage or care, may have rims that have warped or gone out-of-round. Rims in this condition are still usable, but may need shimming in order for the tension rods to function effectively. For shimming instructions, head replacement, Teflon tape purchase, and general maintenance assistance, the following article by Tony Edwards (University of Texas – Austin) is highly recommended: http://perc.music.utexas.edu/Students/FAQ/timpani.aspx