A trainlet is a brief harmonic impulse train particle

A trainlet is an acoustic particle consisting of a brief series or train of impulses. Unlike a grain (single waveform cycle with envelope), a trainlet is a short burst of a bandlimited harmonic impulse train - a buzz waveform. The trainlet’s spectrum contains a fundamental and harmonic partials up to the bandwidth of the buzz, making it inherently harmonically rich. By controlling the fundamental period of the impulse train, the composer sets the trainlet’s pitch. The envelope of the trainlet shapes its duration and amplitude curve. Streams of trainlets produce textures with distinct harmonic character, particularly useful for modeling vocal and resonant sounds.

Examples

A trainlet: fundamental = 200 Hz, duration = 30ms, envelope = Gaussian. The resulting particle sounds like a brief harmonic buzz.

Assessment

What distinguishes a trainlet from a regular grain? What type of waveform does a trainlet use internally, and what does this imply about its spectral content?