The Physics of Vibrato
Vibrato is a regular, pulsating change in pitch that adds warmth, richness, and expressiveness to a sustained note. Technically, it is a frequency modulation -- the pitch oscillates slightly above and below the target note at a rate of roughly 5 to 8 oscillations per second. This is not a conscious wobble but a natural acoustic phenomenon produced by healthy coordination of breath support, vocal fold tension, and resonance. A good vibrato sounds effortless, preventing a sustained note from becoming flat and lifeless.
How AI Replicates Vibrato
Blob Opera's sustained tones have an opera-inspired character that can be used to start a listening discussion about vibrato. Google confirms that the voice model learned from professional singers, but it does not claim that the system reproduces a documented vibrato rate for each voice type. Listen for pitch movement, then compare it with recordings of real singers rather than treating the experiment as a measurement tool.
Why Vibrato Matters for Natural Sounding Synthesis
Vibrato is one of several cues that shape a sustained singing tone, alongside breath, resonance, articulation, and changing dynamics. A steady pitch is not automatically inhuman: singers also use straight tone deliberately. Blob Opera offers an approachable example of stylized vocal sound, not a complete model of healthy singing technique.