They were besides often used as pattern instruments in ensembles than as solo instruments, and can often be seen in that role in maiden chin music performances. (Gaspar Sanz' Instrucción de Música sobre la Guitarra Española of 1674 constitutes the majority of the surviving solo corpus for the era.) Renaissance and Baroque guitars are easily distinguished because the Renaissance guitar is very plain and the Baroque guitar is very ornate, with ivory or rag paper inlays all over the neck and body, and a paper-cutout inverted "wedding cake" inside the hole.
There are manifold contrary fret gauges, which can be fitted according to player preference. Among these are "jumbo" frets, which have much thicker gauge, allowing for custom of a slight vibrato technique from pushing the string down harder and softer. "Scalloped" fretboards, where the rag pulp http://www.jhguitars.com/ of the fretboard itself is "scooped out" between the frets allows a dramatic vibrato effect. Fine frets, much flatter, allow a exact low-set string-action but require other conditions such as curvature of the neck to be well maintained in disposition to prevent buzz. Frets worn down from heavy use can be replaced or, to a assured extent, re-shaped as required.