When I was learning violin, I used to mess around with my violin to understand how it worked (it was a very cheap one). One of the things I noticed was the covering the holes with paper changed a lot the tone of the instrument but very little the power of it.
Also, my violin teacher had a couple of superb (and very expensive) old violin. And there was a lot of variation in the shape of the f from instrument to instrument. Different f-holes give different "character" to the sound but the impact on the power was really limited.
One of the things I noticed was the covering the holes with paper changed a lot the tone of that instrument but very little the power of it.
That's why violin mutes, which allow a violinist to practice quietly, attach to the bridge...to reduce the transfer of vibration to the chamber via the sound post and bass bar...
Also, my violin teacher had a couple of superb (and very expensive) old violin. And there was a lot of variation in the shape of the f from instrument to instrument. Different f-holes give different "character" to the sound but the impact on the power was really limited.