Wim: I had similar problems with our Hamburg D having a string wander here and there and seem to have had good luck with tapping the strings to the front side bridge. I am able to use a flashlight flooding light sideways across the bridge and actually SEE light shining under the string just behind the front bridge pins! I also nudged the plate bolts a bit. We have visiting orchestras that request 442 every few months and I have no real problems raising the pitch the day before and then tuning again the day of the performance as well as after dress rehearsal. I too have heard it is partly to ENSURE the pitch is not BELOW A-440. I can imagine a scenario where groups on tour get tired of finding pianos with low pitch and request 442 just to be SURE it's not low. Several European orchestras violin players have pulled out their own tuning device to check the A as I leave! John Minor University of Illinois
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