While the guzheng is being played the soundboard faces upward, so dust in the air settles on it readily, and the dust between the bridges is especially hard to reach. Do not wipe the soundboard with a damp cloth: a large area of absorbed moisture makes the instrument sound dull. A guzheng cleaning brush removes the dust easily. Nor should you polish the soundboard with wax, which readily causes bridges to shift and jump.
Dust alone does not change the sound — dust mixed with hand moisture does. Settled dust is mostly a matter of appearance. What actually soils the board is dust combining with sweat and humidity into a thin film, and the longer it stays the harder it is to remove. Cleaning is easier as a habit than as a rescue.
Routine dusting: a soft brush along the grain. Work from the treble end towards the bass end and gather the dust at the tail rather than scrubbing across the grain. In the narrow gaps between bridges, blow the loose dust out with an air blower first, then pass the brush over. Do not lift the bridges out to clean under them — once a bridge moves, the tuning has to be redone.
Fingerprints and grease: a barely damp wipe, then dry immediately. For marks on the lacquer, pass a cloth wrung almost dry over the spot and dry it at once, keeping the area and the time as small as possible. Avoid alcohol, scouring powder and washing-up liquid: they attack the finish and leave damage that is harder to fix than the original mark.
No wax. Wax and furniture polish make the surface slippery, so the bridges lose friction and start to shift or jump, taking the tuning with them. Wax also sinks into the grain and is then almost impossible to remove completely. The soundboard needs to be clean, not glossy.
Habits worth more than any cleaner: wash your hands before playing, wipe the sweat off the strings with a dry cloth afterwards, and cover the instrument when it will not be played for a while. Most marks on a soundboard are the accumulation of these three actions being skipped.
If the board already shows discolouration or marks you are unsure about, send us a photo and we will help you tell surface deposits from damage to the finish before deciding what to do.