Yamaha Silent Piano GB1KS Manual

MAINTENANCE HANDBOOK
GB1KS
MHB29
May, 2011

- 1 -
Foreword
This handbook covers maintenance for GB1KS, the Silent Grand Piano released in September
2009.
For additional information, see GPS-GB1 Service manual PP008615
Table of Contents
1. Unit structure and Names ---------------------------------------- 2
2. Adjustment / Checking points ------------------------------------ 4
3. Piano regulation caution -------------------------------------------5
4. Check regulation and Adjustment Silent mechanism -------6
5. Silent let-off Adjustment --------------------------------------------9
6. Sensor Unit Adjustment -------------------------------------------12
7. Maintenance and Test Modes -----------------------------------13
8. Unit Connection Diagram -----------------------------------------16
9. Parts List ---------------------------------------------------------------17

- 2 -
Fig.1
Fig.2
Fig.3
1. Unit Structure and Names
① Switch Box
② Shift Pedal
③ Sostenuto Pedal / Bass-damper Pedal
-Europe: Sostenuto Pedal
-US / CANADA: Bass-damper Pedal
④ Damper Pedal
GB1KS switches Silent / Acoustic mode
with the operation lever and detects key
and pedal movement.
⑤ Key Sensor Unit
-Key sensor unit adjustment ⇒P.12
-Key sensor measurement P.13
⑥ Regulating Rod
-Check/ adjustment ⇒P.8
-Silent let-off adjustment ⇒P.9 - 11
⑦ Hammer Shank Stopper
-Check / adjustment ⇒P.6, 7
Switch Box
-Front side
Power Switch
Reverb Adjustment
Knob
-Right side diagram
Volume Knob
Headphone Jacks
Test Switch -Back side
Pedal Connector
Key Connector
[DC IN 12V] Connector

- 3 -
Fig.4
⑧ Silent Lever
-Stroke adjustment of Silent lever
⇒P.6
⑨ Shift Pedal Sensor
Shift sensor ON/OFF
-How to check / adjust the sensor detection
position
⇒P.14
⑩ Damper Pedal Sensor
Variable Resister (VR) Sensor
ON / Half / OFF
-Damper pedal sensor measurement
⇒P.14
-How to check the sensor detection position
⇒P.14
-Damper pedal sensor position adjustment
⇒P.15
-Bottom face diagram
Switch
B
ox

- 4 -
2. Adjustment/ Confirmation Items
Adjustment item Description Ref. page
Piano regulation caution ・Disengage Silent mechanism
・Disconnect sensor cable
⇒P.5
Silent mechanism ・Check / adjustment ⇒P.6
・Check / adjustment of hammer shank stopper ⇒P.6
・Hammer shank stopper rotation amount adjustment
(Vertical to hammer shanks)
⇒P.6
・Hammer shank stopping position adjustment
5 - 6mm (Normally only checking)
Replace the cushioning only when greatly differing
from standard.
(List of cushioning parts ⇒P.7 )
⇒P.7
・Check / adjustment of the regulating rod ⇒P.8
Silent let-off adjustment ・Level adjustment of the regulating rod
Escapes at the shank stopping position :1 to 2mm
before shank stopping position.
⇒P.9
Sensor unit adjustment ・Key sensor unit adjustment
Gap between the bottom surface of black keys and
the upper surface of key sensor unit when pressing
the black keys to the lowest position : 3.8 to 4.0mm
⇒P.12
・Adjustment of pedal sensor unit ⇒P.12 - 15
Maintenance mode ・Program to adjust the detection position of the key
sensor and damper pedal sensor by measurement.
・Executes measurement after the key sensor
adjustment.
⇒P.13
Test mode ・Program to check the detection position of the key
sensor and damper pedal sensor.
・Measurement result and adjustment status can be
confirmed.
⇒P.14