I requested a quote for the following
which, if I understood correctly the various fields, if for a group of 12 sensorboards for the QRE1113 sensors (without the price for the sensors and assembly). The quote is based only on the fields I filled in this form, no files where uploaded, which surprised me. I may have gotten the "Top SMD Pads" number wrong, and I don't see the number of requested holes (for the connector). The resulting quote is even more confusing
I am not sure if the price is per piece or per array, but I suspect per piece otherwise it becomes really peanuts when ordering many identical ones? In either case, the volume discount is massive, as you can see. Doubling the number of items purchased, almost halves the price of the part!
With 48 pieces (each with 4 sensors) you could do the whole instrument, hammers and keys (assuming the grouping of sections in the piano work out, which they probably won't). So with 96 pieces you could have enough for two pianos. If the price is per piece, ordering sensors for two instruments will cost $435.84 (if the price is per array, it'll cost only 35 dollars which sounds too cheap?).
On the other hand, ordering only one array with only 12 sensorboards (for just 48 keys or 48 hammers, or 24 keys+hammers), so a 1/8 of the previous example, will cost $327.12 if the price is per piece (if the price is per array, it will cost slightly less than 30 dollars). So how you can see, it basically does not matter how many you order….
The assembly costs are a little more sane, but still with massive volume discount. The labor price, in dollars, at 20 day, for the boards above (assuming 4 SMT sensors and one through hole connector per piece) is 106 for one array of 12 pieces, 2x62.13=124.26 for two boards, 4x40.92=163.68 for the "whole piano" and 8x26.57=212.56 for two pianos.
Availability and cost of parts is more complicated to get, so I've not done it yet, but I wanted to share this for now.