oldbayan said:I have done many reed transplants between accordions, also complete reed replacements with new sets, and every time there were adjustments required! Do not expect anything to be "straightforward".
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Lastly, be ready to spend a couple of hours fine-tuning the reeds in their new instrument! Tuning reeds is very unforgiving... you need to be very careful. But at the end, it's great fun to give a squeezebox a new life.
Tuning is indeed always quite a bit of work, certainly after a transplant because the accordion body and the reed blocks have significant influence on the tuning. A reed that's perfectly in tune can easily shift 5 cents or even more after transplanting it to a different accordion. Even within the same box: if you for instance take an A (440) from a piccolo reed block (thus that's the lower A) and put it in place of the A on the M reed in cassotto it will go down at least a few cents and be clearly out of tune... Accordion factories use "pre tuners" who prepare the tuning of reeds before they go in an accordion. They use a table of deviations so they tune reeds with a predetermined deviation that will be mostly compensated by placing the reeds on the block in the right position. Once inside the accordion the "final tuner" only needs to make small corrections and can work faster.