The similarity of piano tones recorded on six historic instruments built during the nineteenth century by the Stein-Streicher dynasty is examined from both a perceptual and sound analysis point of view. Six par- ticular notes are investigated from bass (C2) to treble (G6) and for each note, four tones of different fortepianos are compared. A discrimination test is conducted, using a three-alternative-forced-choice (3-AFC) procedure. Results show that listeners can discriminate the tones in the bass (C2, F3, C4) and high treble range (G6) more easily than in the medium and low treble range (A4, C]5). Spectral, temporal and spectro-temporal descriptors are calculated for each piano sample. Correlations are calculated between descriptor distances and the discriminability index d0 derived from the listeners’ responses. Spectral and spectro-temporal cues appear to be dominant in the discrimination of piano tones, although the importance of individual descriptors varies somewhat with the range of the investigated notes (bass, medium, or treble).