| STU C4 262.63 Hz | STE C4 262.63 Hz |
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| STU length: 290cm. 19ribs A STUfor C4: positioned where the C4 trichord strings are coupled to the treble bridge, 164 cm from the rear, 45 cm from the curved front side, 74.5cm from the straight rear side, B STUfor C4: 38cm from the straight rear side. 170cm from the rear end. |
STElength: 273cm. 17 ribs A STEfor C2: positioned where the C4 trichord strings are coupled to the treble bridge, 70cm from the straight rear side, 153cm from the rear end. B STEfor C2: 80cm from thestraight rear side, 25cm from the curved side,110cm from the keyboard. |
| C4 A & B Probe Positions Stuart and Steinway Soundboard Fig 3.9 | |
| STU C5 523.25 Hz | STE C5 523.25 Hz |
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| STU length: 290cm. 19ribs Not done A STUfor C5: positioned where the C5 trichord strings are coupled to the treble bridge, 89cm from the keyboard, 58 cm from the curved front side, 95.5cm from the straight rear side, B STUfor C5: 59cm from the straight rear side. 124.5 form keyboard. |
STE length: 273cm. 17 ribs A STEfor C5 positioned where the C5 trichord strings are coupled to the treble bridge, 85 cm from the keyboard, 59 cm from the curved front side, 88cm from the straight rear side, B STEfor C5: 104cm from the straight rear side. 40cm from the front curved side, between ribs 11-12. |
| C5 A & B Probe Positions Stuart and Steinway Soundboard Fig 3.10 | |
