The SieteQuinto is a unique seven-string guitar, born from the passion and ingenuity of Roberto "ATTO" Castro. Growing up immersed in the sounds of the traditional requinto, a smaller, high-pitched guitar popular in Latin music, Castro envisioned expanding its capabilities for jazz improvisation. He recognized the requinto's limitations for soloing, particularly its lack of deep bass notes. His solution was both simple and revolutionary: adding a seventh string. This innovation transformed the instrument, providing the extended range and sonic depth needed for expressive jazz playing.