What do you want in a bass ?

[Ken McKay]

No I haven't noticed any correlation of F hole size to either volume or depth of sound. This is easy to test if you cover a portion of the soundhole, it either changes or not.

From what I have seen and heard, the things that do seem to matter are f-hole placement. This might be from their effect on the top plate resonances. Of course this is hard to prove. I am thinking that wider spacing effects the depth because of the flexibility of the plate goes up across the grain when spaced wider apart. This would effect depth of sound the most I think if the f holes are wider spaced. But the air inside needs to be able to reinforce the plate movement or it is wasted movement. So air volume and plate resonance needs to match. More of this can be heard as more fundamental to the tone.

Holes in the side of the upper bout don't seem to effect depth or volume much. I have played Arnold's ergo and I heard him say this also.

A hole in a place of maximum rigidity of the plates (tailblock) might theoretically highly effected sound. I have read that air pressure is highest there. Since the air pressure reinforces the plate vibration of both the top and back, a loss of pressure could decrease volume or depth.