VoXtream: Full-Stream Text-to-Speech with Extremely Low Latency

Nikita Torgashov; Gustav Eje Henter; Gabriel Skantze

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arXiv · 2509.15969

VoXtream: Full-Stream Text-to-Speech with Extremely Low Latency

Nikita Torgashov·Gustav Eje Henter·Gabriel Skantze

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Abstract

We present VoXtream, a fully autoregressive, zero-shot streaming text-to-speech (TTS) system for real-time use that begins speaking from the first word. VoXtream directly maps incoming phonemes to audio tokens using a monotonic alignment scheme and a limited look-ahead that does not delay onset. Built around an incremental phoneme transformer, a temporal transformer predicting semantic and duration tokens, and a depth transformer producing acoustic tokens, VoXtream achieves, to our knowledge, the lowest initial delay among publicly available streaming TTS: 102 ms on GPU. Despite being trained on a mid-scale 9k-hour corpus, it matches or surpasses larger baselines on several metrics, while delivering competitive quality in both output- and full-streaming settings. Demo and code are available at https://herimor.github.io/voxtream.

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BibTeX RIS

Nikita Torgashov, Gustav Eje Henter, Gabriel Skantze. 2025-09-19. VoXtream: Full-Stream Text-to-Speech with Extremely Low Latency. https://arxiv.org/abs/2509.15969

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