I want to build a guitar that is filled with water. Basically, it will have a single cutaway and it's hollow. However, instead of air, it will be filled with water. The body will essentially be a guitar shaped water bottle. How will this concept affect the sound of the guitar? My guess is that since vibrations don't like to pass through two different materials, some frequencies will be lost and it will have crappy sustain, but will there any other effects?