In the mid-1980’s, I went on an all day field trip with several dozen students and a few fellow teachers to the Oakland Museum. During a break I was walking in the gardens of the Museum chatting with some of my students, when one bent down and picked up an unusually shaped twig that was lying on the path. She handed it to me and said: “Bob, this looks like something you could use.”
I looked at it from all sides and began to mindlessly play with it as we continued our walk. I quickly found that it was very easy to twirl the twig while holding onto the short hook-like end that had grown at almost a right angle to the rest of the twig.
I absent-mindedly twirled that twig for most of the rest of the day. It was easy, addicting, and the quiet whisper it made as it twirled was intriguing.
When I got home late that night, I kept playing with the twig and noticed how the sound it produced grew louder the faster I twirled it. I started to think about ways to make the sound easier to produce and louder. I suddenly found myself recalling a faint but very fond childhood memory of a simple toy that I had played with in the mid-1940s. It consisted of a small rectangular stiff card with a long string attached to it. The card had small pieces of light wood glued onto two of its edges. A rubber band was stretched around the two pieces of wood. When I swung the string around my head the rubber band would start to make a sound.
That memory quickly led to the addition of a rubber band to the twig. Twirling the twig now generated a very pleasant, even though still rather quiet, humming sound.
I observed that more rapid twirling generated a louder sound. I also noticed that rapid twirling heated up my hand from the friction of the spinning twig and that maintaining my grip was very difficult at faster speeds . It became obvious that a handle which could reduce the friction and provide a better grip would be a big help.
I set the found twig aside and proceeded to construct a Hummer from scratch. I thought that a long dowel with a handle at a right angle should do the trick. Even though the friction problem had been fixed, this version was still awkward to twirl. It took several failed attempts including a lot of broken hummers and the exploration of several variations of the design to recognize what was wrong: the handle did need to be at a right angle, but not a right angle to the hummer shaft, it needed to be at a right angle to the plane of twirling!
Now the Hummer looked like a long skinny triangle. The balance was great. It took much less energy to twirl for long periods of time and it was now possible to have very long twirling sessions without fatigue. This design positions the twirler’s hand and the weighted end of the Hummer directly in line with each other.
Besides the improved action, this alignment reduces the stress at the spot where the handle and shaft meet – the very spot where earlier versions often broke.
Once I felt I had found the correct design I started collecting sturdy twigs that had naturally grown in the desired configuration. Ever since then I keep an eye out for Hummer frames whenever I am doing any pruning. The raw hummers below came from birch and plum trees in my yard.
Rubber Band Alignment, Airflow and Tuning
It was apparent that rubber bands yielded the richest tones when they were taut, without any twists, and aligned so that the thin side faced directly into the wind allowing the air to pass over and under as the Hummer twirled.
By experimenting with a variety of supports to help stretch and align the rubberband, I discovered that it is possible to stretch the rubberband in such a way as to create the potential for two different pitches and at the same time separate the two sections of rubberband and position them for maximum airflow.
I first tried using wooden pegs to separate the two sides of a stretched rubberband, but these did not create a wide enough gap and could not be easily repositioned. I tried a variety of metal screws and brackets. Then one day when I was looking around my workshop I came across a jar full of Hoffman Hose Clamps. (Note: These are available from chemistry lab equipment suppliers.)
Creating two distinct pitches is accomplished by making one length of the rubber band tighter than the other when stretching it around the clamp.
These clamps turned out to be a great solution: they provide a way to position the two sections of rubber band so that neither one is directly in front of the Hummer shaft allowing the air to flow freely over each part piece of the rubber band. In addition, the clamps are easy to re-position on the Hummer shaft by simply loosening the clamp and sliding it to a preferred spot, and they provide a bit of weight that helps to make the twirling easier and steadier.
I use all of the following:
- both sides tuned to the same pitch (this precludes the de-tuning effect).
- one side tuned a minor third or a fifth above the other side.
- one side tuned to five semi-tones below the other side.
- random: just quickly stretch the rubberband around the clamps and listen.
De-tuning and Listening
Even a well-tuned rubber band will begin to loosen and become de-tuned during long twirling sessions. It is usually the tighter section of rubber band that loosens and becomes gradually lower in pitch. As the two sides of the rubber band move towards the same pitch, the overtones begin to change. This makes for some of the most fun Hummer listening. You can hear some of this happening in the audio sample below.
After a few hours of use, rubber bands age and lose a lot of their elasticity becoming too stretched out to be tuned and, in the process, become too quiet. Changing rubber bands is therefore necessary every few hours of twirling to keep a nice range of overtones to maintain a nice bright sound. The sounds are especially sweet when a new rubber band is used for the first time.
I have had best luck so far with #73 size rubber bands available in most office supply stores. I buy them by the boxful.
To keep the Hummer handle from squeaking, I slip some candle wax shavings into the hollow handle.
I always slip the rubber band off the clamps when the Hummer is not in use.
I have experimented with decorating Hummers, including wrapping the shafts with colored yarn or using painted handles and end-weights as well as using a variety of found objects to serve as weights and/or handles. This can sometimes generate interesting rings of color as the Hummer is twirled, but the sound is so much more powerful than any visual effect that I no longer worry about how a Hummer looks – only about how easy it is to use and how it sounds. Anyway, my eyes are usually closed while twirling the better to concentrate on the humming.
Using the Hummer
One of my favorite ways to use the Hummer involves twirling while studying a painting or sculpture that is in progress (or any other project I happen to be working on that is in need of some pondering). I used a Hummer for countless hours during the 3 to 4 years when I was painting the four triptychs in NFMOA. As I looked at my paintings and listened to the droning going on and on, and on and on, I would often feel myself slipping ever-so-slightly into a state of timelessness and could focus my attention on the ever-changing harmonics in the Hummer’s sound.
The other application of Hummer twirling I especially enjoy is to use it in an active chakra meditation. I consciously select a direction to face. This makes me mindful of magnetic North and the spinning of our planet as a background to and context for the twirling Hummer. I usually face North. I begin twirling the Hummer in front of my chest so its circles are parallel to my body with a vertical plane-of-twirl. Once I have established a nice steady pace, I lower the twirling until the center of the twirling, the handle, is directly in front of my first or lowest chakra and I twirl for a while focusing on the harmonics in the Hummer’s sound. At spontaneous intervals I slowly reposition the Hummer until it is in front of the next chakra working my way up until I eventually am twirling the Hummer over the top of my head.
This exercise directs and maintains my awareness and focus on the center of the twirling as well as on the twirling itself and the sounds it makes.
The final twirling position, above my head, produces an intense stereo effect, a kind of Doppler effect as the Hummer passes close to one ear and quickly fades then passes close to the other ear and quickly fades all in rapid succession. Over and over and over…
In the twirling meditation described above, the biggest challenge is keeping the plane of twirling perpendicular to the floor, parallel to one’s torso, then ending with it over the head with the twirling plane parallel to one’s shoulders. Another challenge is learning how to keep a steady tempo. This becomes essential as the twirling grows increasingly difficult due to arm fatigue. One method I developed to deal with these challenges is to switch hands mid-twirl causing as little change in the tempo or overtones as possible. The longer one focuses on the droning hum and the fluctuations in the overtones and change in pitch arising from the loss of tuning and rubber band fatigue the more amazing the experience of listening becomes. The Hummer is truly a great and simple sound toy.
The audio example below begins with each of the two lengths of rubberband being plucked to demonstrate how the Hummer was tuned at the time. The pitches sound very close to D-2 and G#(Ab) seven semitones below. The D is especially complex and is combined with several D# harmonics. As the twirling picks up speed you can hear the D glide into a strong D#(Eb). (Note: the pitch references are just my best guesses at parts of two very complex sounds.)
Listen to The Hummer:
Trial and Error
Many versions and variations were tested before finally arriving at the optimum size and functionality. In one disastrous experiment I installed a large weight at the end of a 3-foot long Hummer. This one had a very large library-sized rubber band and generated a wonderful deep tone, but it took a lot of muscle power to keep it twirling for long periods of time. On one occasion, in mid-twirl, the weight flew off the end and the Hummer suddenly snapped in two. That was the end of that particular avenue of investigation. Bigger was not better.
Another example of learning the hard way had to do with developing the proper Hummer twirling technique. I quickly discovered the importance of paying attention and staying focused especially when twirling the Hummer around my head. On one such occasion I became absorbed in listening to the Hummer’s sound when the end of the Hummer, at full speed, smacked me in the back of my head. After that, I became much more alert and aware of exactly how and where the Hummer was positioned at all times. This reduced the number of head-smackings, but did not completely eliminate them. Every once in a while when I let my attention drift just a bit… WHAM!
After much trial, and sometimes painful error, I arrived at the current optimal form. It is strong, light-weight, easy to use, and nicely balanced making it possible to twirl for very long periods of time.
If you make your own Hummers or know of any other hummer designs, please let me know. I would love to see photos and will be glad to post them here.