Given the choice between nylon and gut, many luthiers prefer to use gut, as it conforms more readily to the sharp angle at the edge of the fingerboard.
Soundboard thickness varies, but generally hovers between 1.5 and 2 millimeters.
Some luthiers tune the belly as they build, removing mass and adapting bracing to produce desirable sonic results.
As the wood suffers dimensional changes through age and loss of humidity, it must retain a reasonably circular cross-section to function properly—as there are no gears or other mechanical aids for tuning the instrument.
Often pegs were made from suitable fruitwoods such as European pearwood, or equally dimensionally stable analogues.
Modern manufacturers make both gut and nylon strings, and both are in common use.
Gut is more authentic for playing period pieces, though unfortunately it is also more susceptible to irregularity and pitch instability due to changes in humidity.
The bridge is made so that it tapers in height and length, with the small end holding the trebles and the higher and wider end carrying the basses.
Bridges are often colored black with carbon black in a binder, often shellac and often have inscribed decoration.
The sound hole is not open, but rather covered with a grille in the form of an intertwining vine or a decorative knot, carved directly out of the wood of the soundboard.