Giovanni Girolamo Kapsperger (ca. 1580-1651), one of the most renowned musicians of early 17th-century Rome, gave a decisive impulse to the development of the solo repertoire for chitarrone (now called theorbo), and his tablatures occupy a central place in this repertoire. However, some passages of his work are considered today as counterpoint errors or writing oversights: nowadays, musicians do not hesitate to ignore the interpretation instructions indicated in the prefaces of his solo books. We hypothesize that these passages may in fact constitute sound experiments directly related to the specific characteristics of the instrument and the research of the stilo moderno. To this end, we examine Kapsperger's surviving publications for solo chitarrone and compare them with important period tablatures and some solo keyboard works. This confrontation, supported by a consideration of the principal literature currently available on the subject, aims to produce a better understanding of Kapsperger's solo work, as well as, more generally, of chitarrone tablatures of the period, and to provide elements likely to inspire and enrich today's theorbo practice.