Speech-to-Speech

Speech-to-speech generates spoken audio directly from spoken input — you talk, the system talks back — without a person ever seeing the text in between. It powers two big use cases: real-time voice agents that listen and respond conversationally, and speech translation that takes English audio in and returns Spanish audio out, sometimes preserving the speaker's tone. Traditionally this was a pipeline of speech-to-text, an LLM, then text-to-speech; newer end-to-end models (like Meta's SeamlessM4T, or realtime voice APIs) cut latency by skipping the text round-trip. For SaaS builders, speech-to-speech is how you add a natural-feeling voice interface to a product — support lines, language tutors, accessibility tools. Practical note: latency is the make-or-break metric; anything over roughly a second of delay breaks the illusion of conversation, so budget for streaming, interruption handling ("barge-in"), and network jitter. Pipelines are easier to debug; end-to-end models feel more human.