Classical guitar for repertoire of all periods is sometimes critically viewed: Torres and post-Torres style modern guitars (with their fan-bracing and design) have a thick and strong tone, very suitable for modern-era repertoire. However, they are considered to emphasize the fundamental too heavily (at the expense of overtone partials) for earlier repertoire (Classical/Romantic: Carulli, Sor, Giuliani, Mertz, ...; Baroque: de Visee, ...; etc.). "Andrés Segovia presented the Spanish guitar as a versatile model for all playing styles" to the extent, that still today, "many guitarists have tunnel-vision of the world of the guitar, coming from the modern Segovia tradition". While fan-braced modern
Ten-string classical guitar of Yepes Ramírez III considered adding sympathetic strings to the classical guitar. He sought advice from the leading classical guitarists of the time, notably Andrés Segovia and Narciso Yepes, both of them players of Ramírez six-string guitars. Eventually they came up with a ten-string guitar. In "Ser Instrumento", Yepes mentions that the reasons that led him to carry out the "design" ("diseño"), of his instrument were acoustical/physical (""físicas"") and musical (""musicales""). After some "initial protest" that the 10-string guitar envisioned by Yepes was "impossible" to construct, Ramírez agreed to the commission and completed the first of these instruments in March 1964. Yepes