Hey, I have just closed up a Zebrano Hauser classical and was fine tuning the frequency responses. I think I am about right now but I have still not added a bridge. Anyway, the first plot is the closed box.
Main air is close to 100Hz
It looks like I have a very high main top (T(1,1)2)
And not registering a back
However, I knew I had to add mass to the top when I add the bridge and that will lower T(1,1)2. So I added 18gms of bluetac at the bridge location and tested again.
Now my top is too low at around 175Hz and the back has shown up at around 235Hz. But I think that once I add the mass of the bridge but also take into consideration the additional stiffness achieved by gluing across the braces will place me somewhere above 175HZ. It will be interesting to see how much. I also have the option of a lighter bridge if I need to raise T(1,1)2 to 190 and hopefully push up the back to closer to 240Hz, my target frequencies.
Cheers
Dom
looking forward to seeing what happens when the bridge is glued on