Yamaha Silent SB Series Service Manual page 25

•6 STEP MAINTENANCE for the PIANO TECHNICIAN (Minimum 3 are necessary.)
Check if the hammer shank stopper do not disturb the dampers or hammers
STEP 1
movement during normal playing. --> OK STEP 2
Hammer shank stopper height/lateral adjustment is necessary if any disturbing happens. --> STEP 6
STEP 2
Depress and lock the center pedal to enter silent mode.
Check if the acoustic sound doesn't come out during
playing keyboard with mf (Mezzo forte level). If no
sound comes, then the distance between hammer head
and strings will be within 4.5mm-7mm when the
hammer shank touches the shank stopper cushion.
(Fig. 2) --> OK STEP 3
Shank stopper must be adjusted to the front if the
acoustic sound comes. --> STEP 4
If the balance of the same section is not even (ex. bass),
--> STEP 5
Note: Hammer let off (set off) adjustment must be
1mm wider than the adjusted silent mode distance.
STEP 3
Turn on the POWER and check if all 88 keys sound correctly through headphones. (The standard
volume position is at 3 o'clock.) Depress the right pedal and play some notes to check electronic sustain
function. --> OK, Complete the post-delivery inspection.
Check first that if the gray-scale shutter is damaged by taking out the keyboard when some notes sound
incorrectly. Remove dirty marks if there on the shutter by cloth. --> Refer Fig. 11 --> Test mode and
Key sensor measurement, page 4, 5
STEP 4
By rotating the turn backle (Fig. 1), the both beginning and the end of the hammer shank stopper stroke
can be changed simultaneously. Normal adjustment should be done by this adjustment. In order to get
wider stroke, put the additional felt on the bottom of the pedal lock window. It would be effective for
the old pianos. Correct adjustment makes the turnbackle movement around 8 mm (Fig. 1). --> OK
STEP 3
8mm
Fig. 1
Hammer shank stopper
Fig. 2
SILENT SB SERIES
Turn backle
The position to be glued
the additional felt.
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