Lesson Content

Controlling pronunciation.

Technical terms, brand names, product names, and unusual proper nouns frequently get mispronounced by AI voices. Script-level techniques to correct these include: phonetic respelling in the script (spelling the word as it sounds rather than its standard spelling), adding spaces within a compound word to affect how it's parsed, or using capitalization and punctuation to alter how the AI reads certain terms. Test the specific approach that works for the voice and word in question.

Punctuation for pacing control.

Commas, periods, and in some cases ellipses (…) affect how the AI voice pauses and flows between phrases. Adding a comma where a natural pause should occur, or splitting one long sentence into two shorter sentences with a period, can improve delivery rhythm significantly. Experiment with punctuation placement to find what produces the most natural pacing.

Emphasis and SSML (where supported).

Some platforms and voice systems support SSML (Speech Synthesis Markup Language) tags for controlling emphasis, pitch, and prosody explicitly. Verify whether HeyGen's current implementation supports SSML or other explicit emphasis mechanisms – these can provide more granular control when available, but availability varies by platform and voice.

Iterative refinement workflow.

For scripts with multiple pronunciation or pacing issues, address them iteratively: identify the most significant issues first, adjust, generate a test clip covering those sections, review, then address remaining issues – rather than attempting to fix everything simultaneously before any testing.