Audio Engineering Society Convention Paper Presented at the 124th Convention 2008 May 17–20 Amsterdam, The Netherlands The papers at this Convention have been selected on the basis of a submitted abstract and extended precis that have been peer reviewed by at least two qualified anonymous reviewers. This convention paper has been reproduced from the author’s advance manuscript, without editing, corrections, or consideration by the Review Board. The AES takes no responsibility for the contents. Additional papers may be obtained by sending request and remittance to Audio Engineering Society, 60 East 42 nd Street, New York, New York 10165-2520, USA; also see www.aes.org. All rights reserved. Reproduction of this paper, or any portion thereof, is not permitted without direct permission from the Journal of the Audio Engineering Society. Piano “Forte Pedal” Analysis and Detection Antony Schutz 1 , Nancy Bertin 2 , Dirk T.M Slock 1 , Bertrand David 2 , Roland Badeau 2 1 EURECOM Institute - Mobile Communication Department, 2229 Route des cretes 06904 Valbonne Sophia-Antipolis, France 2 Telecom ParisTech - TSI Department, 46 rue Barrault - 75634 Paris, France Correspondence should be addressed to Antony Schutz (antony.schutz@eurecom.fr) ABSTRACT Pressing the sustain pedal is one of the main musical gestures in a piano performance. It influences the sound produced by the instrument, and consequently the efficiency of any automatic system analyzing it. This paper aims at highlighting several features, observable on piano sounds played with pedal, which could be useful in the task of detecting the sustain pedal, and analyzing notes played while it is pressed. Here, we consider two hypotheses, derived from physical acoustics considerations and signal observations, that could help discriminate between notes played with and without the sustain pedal. First, the sustain pedal is found to increase the decay time of partials. This effects dominates the behavior of the partials, not only in duration but also in terms of spectral evolution. Secondly, when the sustain pedal is used, a noise floor appears, for all notes of the piano. Those two effects are investigated in this work, in particular through a method based on a “harmonic plus noise” decomposition. The possibility to use those features as a base for a detection system is discussed. 1. INTRODUCTION Music transcription is the process of creating a mu- sical score (i.e. a symbolic representation, such as a MIDI file, of the music within) from an audio record- ing. In the traditional sense, automatic transcrip- tion implies the estimation of several features such as the pitch and duration of individual notes. But music can not be reduced to a succession of notes, and an accurate transcriptor should be able to detect other performance characteristics, such as slow tempo variations or, in the particular case of the piano, the use of pedals. Usually pianos have two or three pedals [1], among which the most frequently used is the sustain pedal, also called forte pedal.