The discovery of directional and robust wave manipulation has become a crucial goal in the field of science and technology. Topological pump, as an efficient form of directed energy transport protected by nontrivial topology, has been intensively studied in condensed matter and materials physics. Conventional topological pump schemes are mainly related to topological boundary/defect states in conventional lattices. In this Letter, we introduce the concept of topological pump in moiré superlattices for acoustic waves. Acoustic moiré superlattices support localized bulk states protected by a constant band gap throughout the modulation. Based on topological pump of localized bulk states, compact and nearly independent multi-channel topological sound transport is directly observed by spatial scanning of the sound fields, and its topological robustness is observed in the paths with defects. Modulated by topological transport channels, anomalous refraction, splitting, and helicity transport effects are unambiguously observed in our acoustic experiments. Our results pave the way for more efficient directional wave manipulation, which could lead to advances in communications and information processing.

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• Acoustic wave phenomena
• Topological effects in acoustic systems
• Topological phases of matter
• Transport phenomena
• Acoustic metamaterials
• Moire materials
• Topological materials