Cartesia vs Microsoft Azure Text-to-Speech
Discover the differences between Cartesia and Microsoft Azure Text-to-Speech. Learn about features, pricing, and performance.
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Compare Cartesia and Microsoft Azure Text-to-Speech
Cartesia offers ultra-fast voice generation with a latency of just 90 ms, while also ensuring ultra-realistic voice quality without hallucinations. In contrast, the other provider has a higher latency and less natural voice outputs, making Cartesia a superior choice for real-time applications.
Updated at:
Feb 14, 2025
Features
Cartesia
90 ms + network time
Consistently rated as more natural, expressive, and realistic in blinded human evaluations
Infinite request length
Requires 5-10 seconds of audio
IPA Support, strong contextual understanding
Slider control for speed and emotion + synthetic voice mixing and design
8kHz audio, telephony optimized voices
Real-time generation on-device
21 languages with extensive dialect coverage
Up to 15 on highest self serve tier, custom for enterprise
Microsoft Azure Text-to-Speech
300ms – 800ms
Less depth and reliability ratings in human evals
Limited character count for longer texts
Not supported
Requires a substantial amount of audio data
Less contextual awareness in pronunciation
Limited controls for stability and similarity
Standard audio quality without optimization
No on-device generation available
140
100
Voice Quality Comparison
In the realm of voice quality, Cartesia consistently outperforms Microsoft Azure Text-to-Speech. Cartesia's Sonic model has been rated 4.7 in independent evaluations, while Azure scores lower at 4.38. Cartesia's voices are recognized for their naturalness and emotional sensitivity, making them more relatable in conversational contexts. Furthermore, Cartesia's architecture allows for better contextual understanding, ensuring that challenging content is pronounced accurately, enhancing the overall user experience.
Latency Evaluation
Latency is a critical factor in voice applications. Cartesia's Sonic model boasts a Time to First Audio (TTFA) of just 199 ms, significantly faster than Microsoft Azure's 300 ms. This measurement is derived from the 90th percentile score calculated from 100 TTFA measurements for each provider. Cartesia's architecture, based on State Space Models (SSMs), enables superior latency optimization, ensuring that users experience near-instantaneous responses, which is essential for real-time applications.
Hallucination Rate Analysis
Cartesia's voice cloning technology stands out for its low hallucination rate, providing crystal-clear audio without errors. This is achieved through advanced algorithms that ensure high fidelity and authenticity in voice replication. In contrast, Microsoft Azure Text-to-Speech may experience more inconsistencies in voice quality, particularly in complex scenarios. Cartesia's commitment to eliminating hallucinations enhances user trust and satisfaction, making it a preferred choice for developers seeking reliable voice solutions.
Voice Cloning Showdown
When it comes to voice cloning, Cartesia excels with its ability to create an instant clone from just 5 seconds of audio. This feature allows for unlimited instant voice cloning, making it a powerful tool for developers. In contrast, Microsoft Azure Text-to-Speech has restrictions on cloning capabilities, requiring longer audio samples. Cartesia's advanced embedding technology ensures high-quality voice clones that maintain accents and voice quality, even in noisy conditions. Additionally, Cartesia's voice mixing and design capabilities offer a wider variety of voices for diverse applications.
Voice Design Controllability
Cartesia distinguishes itself by offering unique features for voice design controllability. It is the only provider that allows users to modulate emotion and speed, enabling refined voice adjustments while maintaining a natural sound. Additionally, Cartesia supports localization, allowing voices to adapt to various accents. In contrast, Microsoft Azure provides limited control options, focusing primarily on stability and similarity, which may not meet the nuanced needs of developers seeking dynamic voice interactions.
Cartesia - Advanced AI Voice Capabilities
Cartesia AI offers the fastest voice model with hallucination-free, ultra-realistic voice generation and cloning.
High-Quality Voice Cloning
Cartesia offers high-quality voice cloning that captures emotional depth.
Ultra-Realistic Voices
Experience lifelike voices that enhance user engagement and satisfaction.
No Hallucinations
Cartesia ensures crystal-clear audio with no hallucinations for reliable outputs.
Explore Pricing for Cartesia and Microsoft Azure Text-to-Speech
Cartesia
Free - $0/mo. per month with 10k free credits
Pro - $5/mo. per month with 100k credits
Startup - $49/mo. per month with 1.25M credits
Scale - $299/mo. per month with 8M credits
Enterprise - trusted by Fortune 500 companies
Microsoft Azure Text-to-Speech
Free - 0.5 million characters free per month
Pay as You Go - $15 to $24 per 1M characters to
Commitment Tiers - Starting from $960 for 80M characters
Commitment Tiers – Connected container - Started from $912 for 80M characters
Commitment Tiers – Disconnected container - Starting from $47,424 for 4.8B characters
What Cartesia customers say
Join the growing list of companies opting for Sonic.
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"This partnership represents a transformative moment in enterprise AI adoption," said Melissa Gordon, CEO of Rasa. "By combining Rasa’s strengths in enterprise conversational AI with Cartesia's innovative voice technology, we're fundamentally changing how enterprises can deploy and scale AI assistants across their organizations."
"We're thrilled to partner with Cartesia - their technology has dramatically improved the accuracy and reliability of our call center agents. Beyond just providing best-in-class voice AI, the Cartesia team has been a true partner in helping us transform 24/7 patient support for over 215,000 patients. Their support has been instrumental in making exceptional care accessible anytime, anywhere."
Jeffrey Liu, Founder and co-CEO, Assort Health
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"Together AI's mission has always been to provide developers with the most powerful and efficient tools for building AI applications," says Vipul Ved Prakash, Together AI's CEO. "Cartesia is leading the charge of building efficient, multimodal models from first principles, starting with their Sonic TTS model. By integrating Sonic into our platform, we're enabling developers to create sophisticated multi-modal applications that leverage the most advanced and lowest latency voice model available today, all while maintaining the simplicity and reliability our users expect."