Electronic Tuners
iDrumTune Pro App
Considering that this app was designed for tuning drums and not designed as a timpani tuner, it works well for measuring timpani lug tension and pitch in a controlled environment. This app is a keeper. Please visit Drum Sound and Drum Tuning for more information on how to use this app for tuning drums.
The DrumTune Pro app was tested on a well worn head on 29″ Fiedler Dresden drum at a low F2 (87Hz). It was first tested using the Pitch Tuning function with the Target filter off. It would only register in .5 Hz increments which can be problematic when measuring low frequencies, but it was able to register 87Hz at each lug. The drum was then tuned to a D3. The Spectrum Analyzer (Fig 1) read a very strong principal tone (mode 1,1), the 5th (mode 2,1), the 8va (mode 3,1), and the 10th (mode 4,1). All of the upper partials are very near harmonic.
After playing on the drum for a bit, the Lug Tuning function with the Target filter off (Fig. 2) was used to clear the head on the same low F2 (87Hz. After a few attempts, the closest “0” reading for each lug still generated +0.5 for one lug. The Spectrum Analyzer (Fig 3) again reads a very strong principal tone (mode 1,1), but the 5th, the 8va, and the 10th (modes 2,1 3,1 & 4,1 respectively) are a very proportional to the principal tone. Again, all of the upper partials are very near harmonic.
Tune-bot by Overtone Labs
The Tune-bot, although not designed for use with timpani, can produce satisfactory results for isolating and measuring the frequency at each lug point. It has some very interesting functions like pitch/note mode, which switches between frequency and note name. Filter mode, which acts as a high pass/low pass filter. Difference mode, which displays the difference in pitch between the lug hit and a target value; an analog dial showing the relative difference, is also displayed.
The Tune-bot is designed to clip on the counterhoop (of a smaller diameter drum) and remain stationary when tuning. When doing that with timpani, in order to get it to trigger, you need a high SPL, which produces way too many unwanted partials. A simple work around is to take the clip off and move the bot to each lug point to measure the frequency. It then will trigger at a low SPL.
The Tune-bot does a very adequate job of measuring what it is designed to measure; however, it was primarily designed to isolate and measure only a single note/frequency at a time, not a note with a harmonic series. Your heads have to already be relatively clear or evenly tensioned with a Drum-Dial in order to get consistent and stable readings. You can then use it to get each lug to correspond to a single frequency, which is certainly musically functional, but that doesn’t necessarily guarantee that the upper partials will line up harmonically. When using this device, fine tuning/tempering may still need to be done in order to coax the upper partials into a semblance of “harmonicity.”
What about the Protune Tuner?
In theory, the mechanics of how the Protune tuner works makes complete sense since it measures the vibrational modes of the head and then represents that as a pitch. Unfortunately, the principal tone of a timpano’s spectrum (mode 1,1) decays much quicker than the subsequent overtones often leaving the fifth (mode 2,1) to dominate the spectrum. Users report that the Protune often picks up the fifth (the second mode) more than the first. This happens simply because the second mode is baffled less by the bowl and consequently sustains longer than the principal tone. The manufacturer of the Protune tuner states that repeated striking of the head is necessary for the Protune tuner to function properly. Repeated striking of a timpano in a professional situation, no matter how soft, is not practical. The Protune may in fact function best as a supplemental aid in the ear-training of the young timpanist rather than as tuning device.
When the author lectures on timpani acoustics, he uses a Protune tuner to demonstrate the strength of the second mode or the fifth because it works very well for that. With a Protune tune, if you strike the drum once with a soft mallet, it will/may briefly register the principal tone but it inevitably it reads the fifth within a few milliseconds. The User Tips page on the product website details the shortcomings of the device.
Finding the Missing Fundamental
Electronic tuners that display the octave register as well as the frequency are most useful if you want to measure timpani pitch just for the sake of measuring timpani pitch. This type of tuner is usually able to detect the missing fundamental. Since the harmonic spectrum of a well adjusted timpano can be compared to a harmonic series with a missing fundamental, if you can get the tuner to register the actual pitch as the one being an octave lower than the one you are actually playing, then you know you have clear, balanced or tempered heads. i.e., when you are playing a C3 @130 Hz on your 29” drum but tuner is registering C2 @65 Hz this means that your partials are lined up well. Please see the section on Virtual Pitch and Timpani for more information.