Speech-To-Text
When choosing a text-to-speech API (TTS), developers face crucial practical questions: Which provider delivers the right balance of latency, voice quality, control, and scalability in real production systems?
Speech-To-Text
Automatic speech recognition (ASR), aka speech-to-text (STT) technology, is a constantly evolving field. Knowing which ASR model is right for your product or service can be challenging. CTC, encoder-decoder, transducer, and speech LLMs—each with distinct tradeoffs. What does it all mean? And what do you choose?!
Speech-To-Text
Choosing between AssemblyAI and Deepgram for your speech-to-text needs often comes down to answering these critical questions:
Voice is the most natural way we communicate. As AI continues to redefine the way businesses interact with customers, the ability to accurately and instantly transcribe speech across languages is no longer a luxury—it’s a necessity. Enter Solaria-1, the breakthrough speech-to-text model designed to power the next era of global AI-driven conversations.
Whether you’re developing industry-specific voice agents or delivering high-performance customer experiences, Solaria-1 provides the foundation you need —with unmatched language coverage without compromising on quality or speed.
With best-in-class real-time transcription at an industry-leading 94% WAR (Word Accuracy Rate) in English and other common languages, exclusive support of 100+ languages, 42 of which are unique to Gladia, and ultra-low 270 ms latency, Solaria-1 is setting the new standard for AI-driven voice interactions.
In industries where every word carries weight—whether it’s customer support, financial transactions, or legal transcriptions—precision is key. Solaria-1 is engineered to capture even the most nuanced speech patterns with human-level accuracy, making it the go-to model for enterprises that demand nothing less than excellence.
We deliver industry-leading accuracy of transcription across English, Spanish, and other widely spoken languages while outperforming competitors in complex scenarios such as noisy environments, accented speech, and domain-specific terminology.
To ensure results reflect real-world performance, we benchmarked Solaria-1 using public datasets like Mozilla’s Common Voice and Google’s FLEURS—both designed to challenge STT models with diverse accents, dialects, and audio conditions.
While many providers test only on Common Voice version 16, we evaluated across multiple versions to avoid tuning our model to a single release. We also ran tests using anonymized enterprise datasets from contact center environments, measuring Solaria-1 against each competitor’s most advanced model—beating Deepgram’s English-only Nova-3 with our multilingual model.
In voice AI, latency doesn’t just impact performance—it defines the experience. Whether you're building real-time voice assistants or multilingual support bots, responsiveness is what makes interactions feel natural. Solaria-1 delivers ultra-low latency across the board, enabling smooth, human-like conversations.
To understand how we measure latency and ensure our API delivers the best performance in real-life, enterprise environments, it's useful to make a distinction between two key metrics: latency on interrupt and latency on final, which we break down below.
When a user starts speaking, how long does it take for the AI to begin responding? This is known as latency on interrupt, or Time to First Byte (TTFB)—and it’s one of the most important benchmarks in voice AI. When companies claim their voice tech is “more responsive” or “more natural,” this is the metric they’re pointing to.
Imagine speaking to a voice assistant like Siri and interrupting mid-sentence. The delay before the system reacts? That’s interruption latency. The faster the response, the more human the interaction feels.
With an average response time of 270 milliseconds, Solaria-1 positions itself among the most responsive speech-to-text models available today—delivering fluid, real-time interactions that feel intuitive and immediate, while making sure to strike the right balance between latency and accuracy of transcription across languages.
Equally important is latency on final—how quickly the system delivers a complete transcript once the user finishes speaking. This determines when your downstream AI (like an LLM) can start processing the request.
Solaria-1 delivers final transcripts in just ~698ms, outperforming competitors by more than half a second. That speed can significantly accelerate AI response times, making your overall system feel faster, smarter, and more responsive.
Expanding globally means more than just supporting a handful of dominant languages. It requires an AI model that understands the full spectrum of linguistic diversity and can deliver native-level recognition no matter where it’s deployed.
Solaria-1 is the only speech AI model offering native-level accuracy across 100 languages, including 42 that are completely unsupported by competitors. This includes widely spoken but underserved languages such as:
Being truly multilingual means more than just transcription. Solaria-1 enables real-time code-switching, allowing users to shift naturally between languages—a must for global customer interactions. It also supports real-time translation across all supported languages, helping teams eliminate communication barriers and connect with users anywhere.
Precision in speech AI isn’t just about general accuracy—it’s about being accurate where it matters the most for your business. Solaria-1 delivers best-in-class custom vocabulary and named entity recognition (NER) for real-time applications, allowing platforms to:
Whether handling legal transcriptions, technical support calls, or AI-driven sales conversations, Solaria-1 ensures every interaction is smarter, faster, and more precise.
Large-scale voice AI applications require infrastructure that’s not just powerful, but scalable and reliable. Solaria-1 is built to handle enterprise-level deployments with ease, offering:
As part of the Solaria-1 launch, we’re excited to announce partnerships with two leading developer frameworks in the voice agent space: LiveKit and Daily (the team behind Pipecat).
LiveKit is now using our live translation capabilities in AI-driven applications, while Daily has built a demo chatbot powered by Gladia that can switch languages on the fly—try it out for fun! Our API is now natively integrated with both libraries, all powered by Solaria-1.
Voice AI is transforming industries, redefining customer interactions, and creating new possibilities for automation. Whether you're building multilingual voice agents or embedding speech understanding into your product, Solaria-1 gives you a competitive edge with unmatched speed, accuracy, and language reach.
For developers, Solaria-1 offers plug-and-play APIs, real-time performance, and support for advanced customization—so you can build fast, scale effortlessly, and ship smarter.
For decision-makers, the model delivers enterprise-grade accuracy, global reach, and the infrastructure to support mission-critical applications—now and in the future.
Ready to build the future of voice? Start building with Gladia now or book a demo to learn more.
Gladia is a character from Isaac Asimov’s novel The Naked Sun, a story set on the planet Solaria—a world defined by solitude, advanced technology, and the tension between human and robotic interaction. Gladia, the character, stands out as someone striving to bridge emotional and social gaps, breaking away from the norms of her society to foster deeper human connections.
These qualities that distinguish Gladia—empathy, inclusivity, and ethical consideration—are at the core of what we, as a company, aim to bring into our products and culture.
With the recent release of Solaria, a model designed to bridge linguistic divides across global markets, the company’s story has come full circle. The sci-fi inspiration that helped shape its visual identity continues to influence our mission: building tools that connect people, across languages, borders—and perhaps one day, even beyond.
The team at Gladia remains proud to carry this vision forward, and hope you join us on this cosmic journey to push the boundaries of innovation together.
