What's a Natural Trumpet?

By the late 14th century, metalworkers had discovered how to bend tubing into a tight U-shape without collapsing or breaking it. This technological advance made trumpets more stable and easier to hold while also making it possible to build them at greater lengths.

Why make trumpets longer? Because increasing the length lowers the harmonic series—the series of naturally occurring notes available to the player. This makes the intervals in the upper register—comprised of whole steps and half steps—more accessible, allowing for increasingly sophisticated musical tasks.

These trumpets appeared in many different configurations throughout the Renaissance, Baroque, Classical, and early Romantic periods, and today are collectively referred to as natural trumpets—long trumpets that produce notes without the use of valves or other pitch-changing mechanisms.

Spectral Enrichment

As brass instruments become longer, another acoustical phenomenon begins to occur: the sound wave gradually distorts as it propagates through the tubing. This effect—described as spectral enrichment by music acousticians—is especially pronounced in instruments with long cylindrical tubing and relatively narrow bore diameters. The result is the brilliant, complex, and highly characteristic sound associated with the natural trumpet—a timbre fundamentally different from that of the modern valved trumpet.

It is this timbre that composers such as Handel, Bach, Mozart, Beethoven, Mendelssohn, Berlioz, Wagner, Brahms, and arguably even Gustav Mahler had in mind when they wrote for the trumpet.

Sine wave graph showing amplitude and time (left to right)
Graphs courtesy of Murray Campbell and Arnold Myers

Sine wave in a state of distortion as a result of non-linear wave propogation. In the distorted wave, pressure rises rapidly and falls more gradually, creating the acoustic phenomena of spectral enrichment.

Sine wave in the most extreme state of distortion. This occurs at higher dynmaic levels, where pressure rises very rapidly—producing a shock wave, described as an "N-wave."

Natural Trumpet vs. Bugle

People often mistake the natural trumpet for a bugle. Both are valveless brass instruments, but a natural trumpet is approximately twice the length of a modern trumpet or bugle pitched in the same key. This lowers its harmonic series by an octave, allowing the player access not only to the familiar “bugle notes” in the middle and lower registers, but also to a complete scale in the upper register. As a result, the natural trumpet is capable of far more melodic playing than most people associate with valveless brass instruments.

Harmonic Series of a Bugle or Modern Trumpet Pitched in C

Harmonic Series of a Natural Trumpet Pitched in C

Learn more about the natural trumpet and why it's an ideal teaching tool for beginners