Re: Replace bridge on Octophone
You'd need to get a new bridge made, perhaps slightly higher. Other modifications aren't necessary if you're satisfied with the string spacing at the nut.
Don't put any more tension on the neck and top (not quite sure what you mean by "tighten up the sound"). Very lightly built instrument, neck prone to warpage (happened with mine), small internal braces which won't take more string pressure.
Mine's been quite rebuilt, with a carbon fiber reinforcing bar in the neck and a new ebony fingerboard. It's also had the headstock cracked and repaired. I baby it because it was, after all, a cheapo instrument (sold for $15 new), and despite its attractive looks and sound, not particularly sturdy.
I have mine strung GDAE with the lower two courses in octaves, and it produces a lot of volume. But I'm always sensitive to the fact that it's fragile.
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