The acoustics of the piano: Askenfelt & Jansson: From touch to string vibration: Timing in the action
1930's Haines Brothers Grand Piano Test Repetition Springs - Piano World Piano & Digital Piano Forums
Spring Tool/Hook Piano Action Work - Jack, Hammer, Damper or Repetition Springs | eBay
Piano Regulation - Repetition Lever Height On A Grand Piano Action I HOWARD PIANO INDUSTRIES - YouTube
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Hart Spring Tool- Schaff Piano Parts & Tools
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Spring Tool/Hook Piano Action Work - Jack, Hammer, Damper or Repetition Springs | eBay
Upright and grand piano actions dynamic performances assessments using a multibody approach - ScienceDirect
Piano Regulation - Grand Piano Repetition Spring Adjustment I HOWARD PIANO INDUSTRIES - YouTube
Construction – Upright Piano
Grand Piano Repetition Spring Adjustment | Howard Piano Industries
Regulating and Voicing a Grand Piano - GLENN'S PIANO SERVICE
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What's A Wippen? - Eric Johnson Pianos
Thomann Online Guides Principles of Tone Generation Acoustic Piano – Thomann United States
Seiler SMR - PianoWorksPianoWorks
Robert Callaghan, RPT
Techniques – Seiler Piano USA
Why does an upright action need springs? - Piano World Piano & Digital Piano Forums
The Piano Deconstructed
Renner Tools - Renner USA
D Type Spring & Loop Grand Action
