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Sonata for Piano Four-Hands in D Major / D-Dur, K. 381/123A: I. Allegro (Secondo - Metronome: 1/4 = 112 - A' = 443 Hz - With 1. Repetition / mit 1. Wiederholung) by Play It on Amazon Music - Amazon.com
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7: Typical modern grand piano action mechanism: key (1), whippen (2),... | Download Scientific Diagram
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7 Illustration of the function of the piano action at successive stages... | Download Scientific Diagram
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Blog: Regulation & Voicing: WHAT BUYERS OF PERFORMANCE-QUALITY PIANOS SHOULD KNOW — Piano Perfect LLC
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