Daily Papers — 2026-09-29
2 papers on audio, speech, music, and acoustics.
1. Louder, Longer, Livelier: Acoustic Shortcuts and Underspecified Rationales in Speech LLM Judges
Authors: Mingyue Huo, Shivam Mehta, Bhavin Jawade, Yinghong Lan, Haoqi Li
Categories: eess.AS, cs.SD Score: 5.95/10 (Obj:7 Id:5 Ind:7 Comp:7 Eff:6 Nov:5 Rep:6)
- Strength: 用 padding/repetition 时长控制干净地拆出内容丰富度偏好，在论文的 ASSET 句对上评委 $0.707$ 对人类 $0.547$，且”不要受长度影响”的提示也只降到 $0.695$。
- Weakness: 标题主打的响度捷径在人类校准下不成立（评委 $0.578$ < 人类 $0.612$），评委只覆盖 Qwen2.5-Omni 与 Gemini 两个家族，缺神经 MOS 这个最小基线。
- Full review: Claude Code 全文七公理审稿
LLM-as-a-judge is widely used for evaluating text, but extending this paradigm to speech requires models to interpret acoustic as well as linguistic evidence. This introduces a modality-specific risk: a speech judge may treat a perceptually salient cue as evidence of quality even when that cue is irrelevant to the target criterion or receives more weight than human listeners give it. We call this behavior an acoustic shortcut. To study it, we audit six speech LLM judges using controlled manipulations of intensity, content richness, and emotional delivery. We evaluate both pointwise scoring and pairwise comparison, using human preference calibration to interpret the results. The judges consistently reward louder audio, prefer content-rich speech more strongly than human listeners do, and map emotional delivery into quality preferences. These effects are most visible in pairwise comparison, while pointwise scores often obscure them. More concerningly, the accompanying rationales rarely identify the acoustic cue that changes a judgment and instead repeatedly rely on a limited vocabulary, leaving them acoustically underspecified. Together, these findings show that reliable speech judges must both resist acoustic shortcuts and ground their rationales in the acoustic evidence behind their decisions. To support reproducibility and future audits, we also release SpeechJudgeAudit, the controlled stimuli and evaluation tools used in this study.
2. Interpreting and Evaluating Dynamic-Rate Speech Codec Boundaries
Authors: Han Wang, Jiaqi Li, Yingda Shen, Yuxiang Wang, Zhizheng Wu
Categories: cs.SD | 5pages, 3 figures Score: 5.63/10 (Obj:7 Id:5 Ind:6 Comp:7 Eff:5 Nov:5 Rep:6)
- Strength: 在固定 FlexiCodec 接口下系统比较 7 种边界规则，4.47 Hz 时参考音节切分把重建 WER 从 Uniform 的 17.61% 降到 13.85%。
- Weakness: 对齐—重建相关只有 n = 7 且未报显著性，PESQ 等不利指标未进相关表，干预实验无方差、无听测，也没有不依赖转录的音节分割器对照。
- Full review: Claude Code 全文七公理审稿
Dynamic-frame-rate neural speech codecs replace a uniform frame grid with variable-duration tokens, making boundary placement part of the representation itself. Yet it is unclear what these boundaries encode and whether interpretable boundaries are also useful for neural speech reconstruction. This work combines boundary interpretation and controlled reconstruction analysis by comparing predicted boundaries with linguistic and acoustic references. We find that boundary meaning depends on the underlying speech representation. For the ASR-oriented SenseVoice and Whisper encoders, shallow layers emphasize phonetic, voicing, and acoustic transitions, whereas deeper layers shift toward syllable and subword structure. In a comparison of six dynamic-frame-rate algorithms and a uniform (fixed-frame-rate) baseline, higher-level linguistic alignment is associated with lower pooling distortion and better reconstruction from semantic tokens. Frame-rate-matched boundary tests make the distinction concrete: a syllable-derived partition improves over both Uniform and Similarity, while a phoneme-derived partition does not improve over Uniform. We infer that for semantically rich speech representations, useful codec boundaries are best understood as allocation decisions organized around the syllable scale.