Step Audio 3 Operational

StepAudio 3 is StepFun's family of large-scale speech models, comprising five models: Realtime, ASR, TTS, Gen, and Music. Realtime achieves 99.7% speech reasoning accuracy, and ASR has a 1.7% word error rate, ranking first worldwide on the Artificial Analysis leaderboard. StepAudio 3 can understand and speak, as well as interpret emotional tone, perform complex reasoning, generate voices and sound effects in a unified manner, and participate in the full music creation process. It supports scenarios including real-time conversations, subtitle transcription, film and TV dubbing, and music production.

Realtime conversation: Supports native full-duplex interaction, understanding, thinking, judging conversational timing, and executing tasks.
ASR speech recognition: Accurately transcribes Chinese, English, dialects, and mixed Chinese-English speech while understanding technical terms and complex contexts.
TTS speech synthesis: Generates human-like speech and reproduces tone, emotion, pauses, laughter, hesitation, and other paralinguistic details.
Gen audio generation: Generates voices, sound effects, ambient sounds, and background music in one pass, with fine-grained control over the timing of each element.
Music creation: Supports generation from scratch, accompaniment for a cappella vocals, song covers, and multi-turn collaborative creation using ABC notation.

Realtime: Uses a native full-duplex architecture in which listening and speaking occur in parallel. During continuous conversations, the model simultaneously understands audio, reasons, and generates speech, supporting parallel reasoning and generation as well as asynchronous Tool Calls.
ASR: Combines high-precision speech recognition with a large language model. The model's contextual understanding, knowledge, and reasoning capabilities correct homophones, names, locations, and technical terms, upgrading transcription from “sound-to-text” to “contextual understanding.”
TTS: Uses a streaming generation architecture to generate and play audio simultaneously, meeting the low-latency requirements of real-time interaction. It also models voice timbre, intonation, rhythm, and breath pauses, and autonomously adjusts emotion and tone based on semantics.
Gen: Replaces traditionally separate dubbing, sound-effect, and scoring workflows with a unified model. Based on natural-language descriptions and reference audio, it generates multiple sound layers simultaneously and participates in sound design through the temporal arrangement of dialogue, sound effects, and ambient sounds.
Music: Supports both generation from scratch and conditional creation. By understanding musical elements in a cappella vocals, lyrics, and melodies, it provides structured control through ABC notation, models song sections, melodic development, and changes in energy, and outputs complete compositions.

Visit the official website: Visit the StepAudio 3 homepage at https://static.stepfun.com/blog/stepaudio3/ to learn about each model's capabilities.
Choose a model: Select Realtime, ASR, TTS, Gen, or Music based on your needs.
Enter the experience center: Visit the StepFun Audio Experience Center at https://www.stepfun.com/studio/audio to try each model online.
Register on the open platform: Go to the StepFun Open Platform at https://platform.stepfun.com/, register an account, and obtain an API Key.
Read the API documentation: View request parameters and usage examples on the integration guide page for the relevant model on the open platform.
Integrate and call the API: Follow the documentation to integrate the API into your application and generate results by submitting text, audio, or natural-language descriptions.
Debug and optimize: Adjust parameters such as voice, emotion, speaking rate, and structure based on the output until it meets your needs.

Strong leaderboard performance: Realtime's speech reasoning accuracy (99.7%) and ASR's word error rate (1.7%) both rank first worldwide on Artificial Analysis, backed by independent third-party results.
More human-like interaction: It senses tone, emotion, and conversational timing, knowing when to respond, when to wait, and how to handle interruptions.
Can converse and get things done: Reasoning, tool calls, and long-running tasks can run asynchronously in the background without blocking the current conversation, turning a voice assistant from a chat tool into a capable task assistant.
One model handles the entire audio pipeline: Dubbing, sound effects, ambient sounds, and music originally required multiple specialized tools. Now, a single generation produces complete sound layers and precisely arranges when and in what order each type of sound appears.
Users retain creative control: Supports multiple input methods, including a cappella vocals, lyrics, melodies, and ABC notation. The AI helps extend and refine the work.

Learn about the product: Visit the StepAudio 3 homepage at https://static.stepfun.com/blog/stepaudio3/ to learn the capabilities of Realtime, ASR, TTS, Gen, and Music.
Try it online: Enter the StepFun Audio Experience Center, input text or upload audio, and experience each model for free.
Register on the platform: Create an account on the StepFun Open Platform, create an application, and obtain an API Key.
Read the documentation: Open the integration guide for the relevant model to learn the endpoint, request parameters, and billing method.
Make a call: Submit text, audio files, or natural-language descriptions through an API request to obtain speech synthesis, recognition, or generation results.
Optimize parameters: Adjust parameters such as voice, emotion, speaking rate, language, and sound arrangement based on the output.
Integrate and launch: Embed the API into your product or workflow, deploy it, and continuously monitor performance.

Official website: https://static.stepfun.com/blog/stepaudio3/

Intelligent customer service and voice assistants: Full-duplex real-time conversations can sense user emotions and execute tasks asynchronously, making customer service communication more natural and efficient.
Meeting minutes and subtitle generation: ASR accurately transcribes long audio and multi-speaker conversations, automatically identifies technical terms, and directly generates meeting minutes or video subtitles.
In-vehicle voice interaction: Supports noisy environments, dialect accents, and mixed Chinese-English speech with low-latency responses, improving voice control while driving.
Film, television, and spoken-content production: For radio dramas, audiobooks, and animation dubbing, it generates voices, sound effects, ambient sounds, and music in one pass, eliminating multi-tool coordination and post-production mixing.
Music creation and cover production: Automatically arranges and orchestrates music from a cappella vocals, or extends lyrics and melodies into complete songs, helping musicians quickly produce demos and finished tracks.