Speech Customization

The Astromech Vocalizer features customization options for creating a unique droid:

Vocabulary

The smallest building blocks of the vocalizer's speech are called phonemes. The Astromech Vocalizer lets users shape the droid's vocabulary by prioritizing or deprioritizing phonemes by category. This can produce a droid that communicates exclusively in beeps, or a droid that never whistles or chirps.

Pitch

Pitch shifting in the Astromech Vocalizer is achieved through a formant-preserving pitch shifting algorithm. This technique is significantly more advanced than traditional pitch shifting methods and produces a more natural voice.

A crude pitch shifter simply retimes a sound. This has the side effect of altering the sound's duration (think fast-forward on a cassette tape).

An improved pitch shifter alters pitch without altering the sound's duration. However, it also shifts the formant, which is like resizing the vocal tract. This makes a voice sound like it's coming from a very small or very large creature.

The pitch shifting algorithm used by the Astromech Vocalizer shifts the pitch independently of the formant. The result is a voice that, when shifted upward, sounds like a regular astromech who happens to have a high voice, as opposed to a miniature creature with a tiny vocal tract.

On the embedded platform, each vocalizer software file contains one pitch. The .hex file you choose to install during software setup determines the pitch of your droid.

Drawl

Drawl affects the astromech's overall rate of delivery. This causes reduction/prolongation of both the phonemes themselves and the spacing between them. Because the Drawl effect is achieved through sample rate conversion, it also impacts the astromech's pitch.

Speed

Speed only affects the spacing between phonemes. A droid with a slow speed setting will pause longer between phonemes, and vice versa.

Effects

Realtime postprocessing effects provide further treatment to sounds produced by the speech AI.