📝 SummarXiv

Abstract

Recent advances in large language models have attracted significant interest in extending their capabilities to multimodal scenarios, particularly for speech-in speech-out conversational systems. However, existing multimodal models handling interleaved audio and text, such as MOSHI require complex multi stage training pipelines, incurring substantial computational costs. Moreover, these models uniformly apply autoregressive generation to both text and audio tokens, overlooking a fundamental asymmetry in their dependency structures: while text tokens exhibit strong target target dependencies requiring causal ordering, audio tokens are predominantly driven by source target dependencies, where audio outputs primarily condition on source text rather than preceding audio tokens. In this work, we propose TtT, a unified audio-text modeling framework that integrates AR text generation with non-autoregressive audio diffusion within a single Transformer architecture initialized from a pretrained LLM.