C5 Directivity

The maximum SPL of the note C5, for each of the three velocity strikes, radiated from the Stuart piano to mic2, 45° from the pianist, and from the Steinway piano 180° away from the pianist, to mic 6.

The radiation pattern for C5 is exactly reversed from that of the note, C2, where the Steinway radiated maximum SPL to mic2, and the Stuart to mic6.

This section will discuss the qualities of the C5v81 radiations in both directions of mic2 and mic6.

The Steinway sound radiated maximum SPL to mic 6 and the Stuart to mic 2. The very marginal difference of volume of 1dB for C5v81, at mic2, was larger for the slower softer velocity strikes, the Stuart was 3dB louder at v20 , and 4dB louder for v54. Mic 6 captured a much wider contrast in SPL. The Steinway piano was 10dB louder than Stuart at mic6 for both v20 and v81, and 8dB at v54.

The instrumental volume of C5v81 was similar, for both pianos. mic7: STU 96 dB , STE 97 dB

The Steinway soundboard vibrated a significantly larger amplitude of the fundamental frequency, than Stuart for the note C5v81. The Stuart soundboard vibrated a larger 2nd partial. Steinway s/board also produced larger 3rd, 4th 5th & 6th partials. Overall the Steinway soundboard vibrated 44% more actively than the Stuart soundboard for C5v81.

For the note C5, the diameter of the Paulello-Stuart wire is .35mm thicker, the tensile strength of the Paulello/Stuart wire is 138 N/mm² higher. The Paulello-Stuart wire for C5 is 4.5mm longer, and is set at 7kg higher tension. The yield or capacity of the Paulello-Stuart wire is approximately 10% higher than the Roslau-Steinway wire.