Xuanjun Chen

Xuanjun Chen (陳炫均)

Ph.D. Candidate, NTU EECS · Taipei, Taiwan

I am a Ph.D. candidate at National Taiwan University, advised by Profs. Hung-yi Lee and Jyh-Shing Roger Jang. My research focuses on Speech & Audio Processing and Large Language Models, specifically audio under­standing, audio generation, deepfakes, and agentic LLMs. My work is supported by Undisclosed Industry PhD Fellowship,  NVIDIA Academic Grant, and IEEE SPS IEEE SPS Scholarship. I have authored 15+ first/co-first papers in NLP/Speech venues (e.g., COLM, TIST, TASLP, ICASSP, INTERSPEECH, ASRU, SLT), and am a core con­trib­utor to DeSTA2.5-Audio (TASLP) and SUPERB bench­marks (ICLR, ACL Findings). I received an IEEE ASRU 2025 Best Student Paper Nomination, plus ISCSLP 2026 Outstanding Paper and ROCLING 2025 Best Paper awards. I am actively looking for a 2027 research internship!

Feel free to reach out at d12942018 [at] ntu.edu.tw, or find him on LinkedIn, GitHub, and 𝕏.

Research Highlights

See all on Google Scholar or browse by topic.

Speech & Audio Language Models and Generation

Can LLM Agents Automate Reinforcement Learning for Text-to-Speech?

Xuanjun Chen, Zixiong Su, Hao Shi, Chang Zeng, Kai Li, Jyh-Shing Roger Jang, Hung-yi Lee

Technical Report, Oct. 2026

What Does LALM Post-training Learn? Rethinking Audio Understanding and Reasoning Capabilities

Hua-Hsuan Chen*, Xuanjun Chen*, Wei-Chung Lu, Chih-Kai Yang, Yu-Xiang Lin, Sung-Feng Huang, Haibin Wu, Hung-yi Lee

Technical Report, Oct. 2026

DeSTA2.5-Audio: Toward General-Purpose Large Audio Language Model with Self-Generated Cross-Modal Alignment

Ke-Han Lu, Zhehuai Chen, Szu-Wei Fu, ..., Xuanjun Chen, ..., Boris Ginsburg, Yu-Chiang Frank Wang, Hung-yi Lee

IEEE TASLP 2026JCR Q1, IF 5.173 Citations as of Oct. 2026

Towards audio language modeling-an overview

Haibin Wu, Xuanjun Chen, Yi-Cheng Lin, Kai-wei Chang, Ho-Lam Chung, Alexander Liu, Hung-yi Lee

Technical Report, Feb. 202488 Citations as of Oct. 2026

Retrieval and Agentic Large Language Models

MetaBench-Harness: Unlocking End-to-End Optimization of Benchmark Harnesses

Xuanjun Chen, Hua-Hsuan Chen, Wei-Chung Lu, Yinghao Ma, Jyh-Shing Roger Jang, Hung-yi Lee

Technical Report, Oct. 2026

Only Ask What You Don't Know: Grounded Delta Planning for Efficient Multi-step RAG

Wei-Chieh Chou*, Xuanjun Chen*, Jian-Ren Lin, Claire Lin, Hung-yi Lee, Jyh-Shing Roger Jang

COLM 2026Accept Rate 29.1%

CodaRAG: Connecting the Dots with Associativity Inspired by Complementary Learning

Cheng-Yen Li*, Xuanjun Chen*, Claire Lin, Wei-Yu Chen, Wenhua Nie, Hung-yi Lee, Jyh-Shing Roger Jang

ACM TIST 2026JCR Q1, IF 10.7

Audio Deepfake Detection

CodecFake+: Codec-Based Resynthesized Data as a Proxy for Detecting CodecFake Speech

Xuanjun Chen*, Jiawei Du*, Haibin Wu, Lin Zhang, I-Ming Lin, ..., Jyh-Shing Roger Jang, Hung-yi Lee

IEEE TASLP 2026JCR Q1, IF 5.1

Towards Generalized Source Tracing for Codec-Based Deepfake Speech

Xuanjun Chen*, I-Ming Lin*, Lin Zhang, Haibin Wu, Hung-yi Lee, Jyh-Shing Roger Jang

IEEE ASRU 2025Best Student Paper Nomination (Top 2.5%)

Experience

  • : Lead Student Researcher, NVIDIA Academic Grant Program, Taipei, Taiwan
  • : Research Intern, Shanda Group, Tokyo, Japan
  • : Ph.D. in Communication EngineeringCommunication Eng., National Taiwan University ·  GPA 4.3/4.3
  • : M.S. in Computer ScienceComputer Science, National Taiwan University ·  GPA 4.19/4.3
  • : B.S. in Computer ScienceComputer Science, Taiwan Tech ·  GPA 4.11/4.3

Impact & Open Source

Lead & Mentored Projects

  • : [Dataset] CodecFake+ (IEEE TASLP ’26, First Author) Codec-based deepfake speech dataset (31 codecs); 4.3K+ HF downloads ·  HF
  • : [Dataset] DFADD (IEEE SLT ’24, Mentor of 3 students) Deepfake dataset from diffusion and flow-matching TTS; 9.1K+ HF downloads ·  HF
  • : [Model] MTDVocaLiST (ICASSP ’24, First Author) Compact audio-visual sync model distilled from VocaLiST; 29 GitHub stars ·  GitHub
  • : [Model] SingGraph (INTERSPEECH ’24, First Author) Graph-based singing voice deepfake detector; 24 GitHub stars ·  GitHub

Community & Collaborative Contributions

  • : [Model] DeSTA2.5-Audio (IEEE TASLP ’26, Core Contributor) 142 GitHub stars, HF model (28.7K+) and data (11.0K+ downloads) ·  GitHub
    • Prepared training data for audio deepfake understanding as part of an audio LLM project in collaboration with NVIDIA
  • : [Benchmark] Dynamic-SUPERB Phase-2 (ICLR ’25, Task Editor) 201 GitHub stars, 325 HF datasets (289K+ downloads) ·  GitHub
    • One of several task editors, reviewing community-submitted audio understanding tasks in this 180-task speech benchmark
  • : [Benchmark] Codec-SUPERB (ACL Findings ’24 & IEEE SLT ’24, Core Contributor) 310 GitHub stars and a public leaderboard ·  Website
    • Prepared audio event classification evaluation and signal-level metrics for the benchmark and challenges

Selected Honors and Service

See all on the Misc page.

Research and Academic Honors

  • : Industry PhD Fellowship Awarded via competitive global selection by an Industry sponsor
  • : NVIDIA Academic Grant Awarded dedicated GPU compute via competitive selection by NVIDIA
  • : IEEE SPS Scholarship One of dozens of recipients worldwide from the IEEE Signal Processing Society
  • : Outstanding Paper (ISCSLP 2026) Selected 8 out of 110 accepted papers (Top 7%)
  • : Best Paper Award (ROCLING 2025) Selected 1 out of 36 accepted papers (Top 2.8%)
  • : Best Student Paper Nomination (ASRU 2025) Selected 11 out of 447 submitted papers (Top 2.5%)
  • : CTCI Foundation Science and Technology Scholarship Research Scholarship for Overseas Students
  • : Google Student Travel Grant Sponsored by Google Asia Pacific to present at ICASSP 2024
  • : 3rd Place Worldwide, ASVspoof 2021 Challenge On the LA track of ASVspoof 2021 challenge (out of 42 teams)
  • : Dean’s List (3 terms) Certificate of Achievement for the top 5% of CSIE students, Taiwan Tech

Service and Outreach