Audience
Developers building real-time voice AI applications who need ultra-fast, human-like text-to-speech for conversational systems and interactive experiences
About Cartesia Sonic-3
Cartesia Sonic-3 is a real-time, streaming text-to-speech (TTS) model designed to generate ultra-realistic, expressive voice output with extremely low latency, enabling AI systems to speak as fluidly as humans in live interactions. Built on advanced state space model architecture, Sonic delivers high-quality speech while achieving near-instant response times, with audio generation beginning in as little as 40–100 milliseconds, making conversations feel seamless rather than delayed. It is optimized for conversational AI use cases, acting as the “voice layer” for AI agents by converting text into natural-sounding speech that includes emotional nuance such as excitement, empathy, or even laughter. It supports more than 40 languages with native-level voices and accent localization, allowing developers to build globally accessible applications with consistent quality across regions.
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Grok Voice Think Fast 1.0
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Cartesia Sonic-3.5
Sonic 3.5 is Cartesia’s fastest, most natural text-to-speech model, built for expressive, real-time voice generation with sub-90ms latency and native support for 42 languages. It is designed to follow transcripts faithfully, voice confirmation codes, and heteronyms correctly without preprocessing, and stay expressive enough to carry a real conversation. It supports languages intended to deliver native-quality speech. Sonic 3.5 focuses on clean audio across every language and voice, with no artifacts to edit out, making it practical for production voice experiences where quality, speed, and consistency matter. Its expressive conversational delivery provides strong pacing and real emotional range, tuned for support and agent transcripts. Alphanumerics such as order numbers, phone numbers, IDs, and emails are spoken naturally in every language, while context-aware English pronunciation helps words like read, bass, and bow land correctly from the surrounding text.
Learn more about Cartesia Sonic-3.5
Pricing
Starting Price:
$4 per month
Free Version:
Free Version available.
Free Trial:
Free Trial available.
Integrations
API:
Yes, Cartesia Sonic-3 offers API access
No integrations listed.
Company Information
Cartesia
Founded: 2023
United States
cartesia.ai/sonic
Videos and Screen Captures
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Product Details
Platforms Supported
Cloud
Training
Documentation
Live Online
Webinars
Videos
Support
Online
Cartesia Sonic-3 Frequently Asked Questions
Q: What kinds of users and organization types does Cartesia Sonic-3 work with?
Cartesia Sonic-3 works with these users and organization types: Mid Size Business, Small Business, Enterprise, Freelance, Nonprofit, Government, and Startup.
Q: What languages does Cartesia Sonic-3 support in their product?
Cartesia Sonic-3 supports these languages: English.
Q: What kind of support options does Cartesia Sonic-3 offer?
Cartesia Sonic-3 offers support via online.
Q: Does Cartesia Sonic-3 have an API?
Yes, Cartesia Sonic-3 has an API.
Q: What type of training does Cartesia Sonic-3 provide?
Cartesia Sonic-3 provides training in the form of documentation, live online, webinars, and videos.
Q: Does Cartesia Sonic-3 offer a free trial?
Yes, Cartesia Sonic-3 offers a free trial.
Q: How much does Cartesia Sonic-3 cost?
Pricing for Cartesia Sonic-3 starts at $4 per month.
