Vibrato
A small, regular pitch oscillation around a held note that adds warmth and emotion. Natural vibrato is about 5–7 oscillations per second.
Vibrato is the gentle wave on a held note — most clearly heard in opera, but present in pop, rock, country, and almost every vocal style at the ends of phrases. Real vibrato is a natural physiological response: the body relaxes the larynx during sustained pitch, and a small periodic pitch variation emerges. Speed: roughly 5–7 cycles per second for most singers. Depth: typically a quarter-tone to a semitone wide.
Vibrato isn't a "feature" you add — it's the absence of tension. A locked, vibrato-less held note is usually a sign of held breath, jaw tension, or constricted larynx. Train your breath support and release your jaw, and natural vibrato often emerges on its own. Forcing vibrato (jaw wiggle, throat manipulation) sounds artificial and trains in bad habits.
Different genres want different vibrato styles. Country and folk often use a slower, wider vibrato. Opera uses a faster, narrower vibrato with full body resonance. Pop and R&B often use vibrato sparingly, only at phrase ends. Knowing the conventions of the style you're singing matters — but the foundation is always relaxed breath and an open throat. Force-free vibrato is the goal.