# Research Scientist - Audio

**Company:** [Retell AI](https://hotfix.jobs/companies/retell-ai)
**Location:** Redwood City, CA
**Role:** ML Engineering
**Salary:** $225k – $400k/yr
**Skills:** PyTorch, LLMs, Audio Models, Machine Learning, Text-To-Speech, Transcription, Multimodal Systems, Model Architectures
**Posted:** 2026-04-14

> Conducts ML research on LLMs and audio models to enhance real-time voice agents' reasoning, latency, and conversational quality. Prototypes models, designs evaluations, and bridges research to production systems requiring strong PyTorch expertise and experimental mindset.

## Job Description

## Key Responsibilities
- Research & Experimentation – Explore and develop new techniques across LLMs and audio models to improve reasoning, latency, and conversational quality in real-time systems.
- Model Prototyping – Rapidly build and iterate on experimental models and pipelines, turning research ideas into working prototypes.
- Evaluation & Benchmarking – Design novel evaluation frameworks, datasets, and metrics to measure performance on complex, real-world voice tasks.
- Bridge Research to Production – Collaborate closely with engineering to translate research insights into deployable systems.
- Human Feedback Loops – Develop methods to incorporate human evaluation into model improvement, especially for subjective conversational quality.
- Advance the Frontier – Stay at the cutting edge of ML research and bring new ideas into Retell’s product and infrastructure.

## Requirements
- Strong ML Research Background – Worked on advanced ML problems (e.g., LLM pre-training and post training, transcription model training, text to speech model training, or multimodal systems), either in industry or academia.
- Deep Technical Foundation – Comfortable with **PyTorch**, model architectures, and the math behind modern machine learning.
- Experimental Mindset – Enjoy exploring open-ended problems and iterating quickly on ideas.
- Bridging Theory & Practice – Translate research into systems that work in real-world environments.
- Startup-Ready – Thrive in fast-paced environments with high ownership and ambiguity.
- Collaborative & Clear Communicator – Explain complex ideas and work cross-functionally to drive impact.

## Compensation
**Cash:** $225,000 - $400,000 base salary  
**Equity:** Offers Equity  
**Other Benefits:** 100% coverage for medical, dental, and vision insurance; $70/day DoorDash credit; $200/month wellness reimbursement; $300/month commuter reimbursement; $75/month phone bill reimbursement; $50/month internet reimbursement

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