The burgeoning field of voice AI has found its most significant application in managing enterprise calls across vital functions such as sales, marketing, and customer support. Large organizations are increasingly entrusting these interactions to a diverse ecosystem of voice model developers, including ElevenLabs and Deepgram; infrastructure providers like Vapi, Retell, and LiveKit; and specialized customer support firms such as Decagon and Sierra.
Amidst this competitive landscape, San Francisco-based Rime is carving out a niche with its proprietary voice AI models. These models are uniquely trained on conversational data that Rime records itself, a method designed to significantly reduce the customization burden for its clients.
Established in 2022 by former Stanford PhD student Lily Clifford, ex-Amazon Alexa engineer Brooke Larson, and Stanford engineer Ares Geovanos, Rime has invested in building a dedicated recording studio in San Francisco. This approach ensures the collection of high-quality, conversational data, moving away from the common practice of scraping audio from the web.
The startup emphasizes fine-tuning its voice models to master the precise pronunciation of various brand entities and industry-specific terminology. By employing a phoneme-based architecture, Rime’s models can adapt to diverse pronunciations, eliminating the need for customers to retrain models for their particular industry.
Rime announced on Wednesday that it successfully closed a $24 million Series A funding round. This round was spearheaded by M13 Ventures, with additional participation from Twilio Ventures, Corazon Capital, Unusual Ventures, and other existing investors.
Lily Clifford noted that despite advancements in voice AI, many enterprises still favor traditional Interactive Voice Response (IVR) systems. This preference stems from the current limitation of AI voice technology to consistently match the proven effectiveness of IVR.
“The voice technology is still not there to automate the vast majority of enterprise phone calls. LLMs have made it a lot easier to build voice applications that work, but they haven’t changed how it feels to interact. Talking with a voice AI agent is not the most compelling experience for the end user. It’s kinda like a new IVR, but with a better voice,” she stated.
Initially, the startup operated with a pipeline of distinct models for speech-to-text, text-to-speech, and a large language model. However, Rime is now strategically shifting its focus towards developing more sophisticated speech-to-speech models. This pivot aims to achieve lower latency, enhance turn-taking capabilities, and effectively manage challenges such as background noise. Furthermore, this integrated approach is expected to reduce reliance on complex orchestration, simplifying the company’s model management.
Rime currently serves customers across various sectors, including food service, healthcare, airlines, and fintech. The company asserts that its unique training data and model positioning lead to longer call durations for its clients, a factor that has been instrumental in securing enterprise contracts with prominent organizations like Mayo Clinic, Dialpad, Upstart, and Asurion.
With the fresh capital, Rime plans to expand its current team of 35 individuals, with targeted hiring in model development, engineering, and partnerships. The company recently welcomed Rafael Valle as its Chief Scientist, an expert who previously contributed to audio understanding initiatives at Meta Superintelligence Labs and NVIDIA’s applied deep learning audio research team.
Morgan Blumberg of M13 shared his perspective with TechCrunch, stating, “Companies like ElevenLabs have moved into being an orchestration and the application layer, going head to head with the Sierras and Decagons of the world. I think there’s just so much more to be done technically, and Rime’s approach of pushing forward on the best model with low latency and high reliability in a regulated environment stands out.”
This latest funding round follows a $5.5 million seed round that Rime secured last May. As part of the current fundraise, Morgan Blumberg will also be joining the startup’s board of directors.
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