Post date: Dec 06, 2014 1:36:4 PM
This is the most important stage, where I fine tune the back plate to get the desired B1+ frequency. M5 was 335 Hz (at 35% Humidity and 7-7,5% MC in the wood) before I glued it on the ribs, with some minor warping at the upper and lower edges. Gluing the plate to the rib garland straightens out the plate and the real M5 was ~340/345. (calculated). I have now taken down the coupling frequency from 289 to 285. I will leave it for some days to settle and finalize it. Does it look like an Italian arch? I think it does.