Smule Renaissance Small: Efficient General-Purpose Vocal Restoration
Yongyi Zang, Chris Manchester, David Young, Ivan Ivanov, Jeffrey Lufkin, Martin Vladimirov, PJ Solomon, Svetoslav Kepchelev, Fei Yueh Chen, Dongting Cai, Teodor Naydenov, Randal Leistikow
TL;DR
Smule Renaissance Small (SRS) targets robust vocal restoration under compound real-world degradations directly in the complex-STFT domain. It introduces a compact bandwise generator with cross-band attention and per-band synthesis heads, augmented by phase-aware losses and a degradation-robust training pipeline to enable large analysis windows while remaining efficient for on-device inference. Empirically, SRS outperforms strong GAN baselines on the DNS 5 Challenge blind set and closely matches a costly flow-based system, and on the Extreme Degradation Bench it surpasses open-source baselines for singing and remains competitive for speech, despite no speech-specific training. The work also provides a realistic benchmarking resource (EDB) for severe multi-degradation scenarios and demonstrates practical real-time performance on consumer devices, with code and data released under the MIT License to support reproducible research.
Abstract
Vocal recordings on consumer devices commonly suffer from multiple concurrent degradations: noise, reverberation, band-limiting, and clipping. We present Smule Renaissance Small (SRS), a compact single-stage model that performs end-to-end vocal restoration directly in the complex STFT domain. By incorporating phase-aware losses, SRS enables large analysis windows for improved frequency resolution while achieving 10.5x real-time inference on iPhone 12 CPU at 48 kHz. On the DNS 5 Challenge blind set, despite no speech training, SRS outperforms a strong GAN baseline and closely matches a computationally expensive flow-matching system. To enable evaluation under realistic multi-degradation scenarios, we introduce the Extreme Degradation Bench (EDB): 87 singing and speech recordings captured under severe acoustic conditions. On EDB, SRS surpasses all open-source baselines on singing and matches commercial systems, while remaining competitive on speech despite no speech-specific training. We release both SRS and EDB under the MIT License.
