CSM 1B
by Sesame
Sesame's Conversational Speech Model, tuned for natural dialogue.
CSM 1B produces remarkably lifelike conversational speech with contextual breathing and pacing, at one of the lowest per-character prices in the catalog. Serves through OpenRouter's speech API.
More details
CSM 1B by Sesame is a fast-speed AI text-to-speech model. CSM 1B produces remarkably lifelike conversational speech with contextual breathing and pacing, at one of the lowest per-character prices in the catalog. Serves through OpenRouter's speech API. Key capabilities include 274 voices across 12 languages, up to 4,096 characters per request.
CSM 1B is priced at $0.008 per 1,000 characters of input text. You can generate speech with CSM 1B on idapt.app alongside 200+ AI models in one workspace.
Voices
6 · 1 languagesAny of these voices can be paired with CSM 1B. Pick a model for quality and speed, a voice for character and language.
Conversational A
English · Female
Conversational B
English · Male
Read Speech A
English · Neutral
Read Speech B
English · Neutral
Read Speech C
English · Neutral
Read Speech D
English · Neutral
Pricing
Cost per 1,000 characters
$0.008
Typical paragraph (~500 chars)
$0.004
Billed on input text length
Capabilities
Speed
Fast: Low-latency, real-time ready
Emotion Control
Natural delivery only
Max Input
4,096 characters per request
Voices
6 voices · 1 languages
