My first venture into split-tones was over ten years ago for a performance of the piece “Humans in Motion” by Canadian composer Annesley Black. If I remember correctly, there was one single split-tone in my part – one of the ‘easier’ ones – and I practiced really hard to get that note to sound. In the end my hard work didn’t pay off – the split-tone didn’t sound at all in the performance! After the performance I spent several months working every day on split-tones until, finally, I could reliably produce them. Even so, depending on the context, split-tones are among the most fragile and unreliable sounds we trumpeters can produce.
It’s impossible to talk about split-tones without mentioning Rebecca Saunders. In her 20+ year collaboration with trumpeter Marco Blaauw, she has truly become the queen of split-tones and has used this technique (among others) extensively in her remarkable works for trumpet. This year I was very proud to premiere her new split-tone filled trumpet duo “Either or” at the Musikfest Berlin. (Update: watch a video of that performance!)
What is a split-tone?
By carefully adjusting the embouchure, two adjacent notes from a natural overtone series can sound simultaneously. It’s a bit like tuning your radio between two stations so that both come in at the same time.
Because this technique relies on overtones, there are a limited number of possibilities that can be produced. Lower adjacent overtones, where the interval to the next overtone is larger, are generally easier to produce than higher split tones where the overtones are closer together.
For reasons that are currently unclear, the interval of the split tone is not always perfect. Most often, the lower note will go sharp causing the interval to shrink. Despite many years of (successfully!) performing split-tones, I still can’t really control the interval.
- Split tones often sound messy and include other frequencies or “noise” in the interval. In general, the higher the split tone, the noisier they become and the desired interval is less likely to be heard.
- Split tones are very fragile and work best in relatively soft dynamics.
- Producing the split tone ‘on demand’, achieving precise intervals and moving from one split tone to the next are a big challenge. These difficulties should certainly be taken into account when composing for this technique.
- The top note of a split-tone is the most important – if split-tone isn’t speaking properly, its the top note that will probably sound on its own.
Moving from one split tone to the next is challenging, but possible. Keep in mind that split-tones may take time to speak, meaning shorter note lengths should be avoided. Both slurring and articulating the pitch changes are possible, though I find slurring a bit easier.
It is possible to transition seamlessly between normal tones and split tones. As I wrote above, the top note is the most important; because split-tones are played from the top note downwards, transitioning to and from that note will sound the smoothest.
Transitioning seamlessly to or from notes outside of the split-tone interval is also possible.
By partially depressing one or more of the valves, a unique sound can be created on the trumpet. I will go into half-valve playing in more detail in an upcoming post. Combining split-tones with half-valve can produce the split-tone effect with intervals otherwise not possible with conventional split-tones. The result is difficult to predict or control, but sounds quite cool!
Stay tuned for an upcoming blog post where I will cover another way to produce multiple pitches at once using the voice!
As you can already see in the examples above, notating a simple diad with normal note heads should be enough to indicate split-tones, though its always helpful to make a note in the legend or directly in the score that a split-tone is intended. Saunders adds a thin vertical line to the right of the diad for her split-tones, indicating the “dirty cluster” effect this technique sometimes produces.