"First developed in the Seventies, the Professional Series product line were the first classical guitar and lute sets to be offered in a wide variety of gauges. They have been acclaimed by concert guitarists, lutenists and prominent teachers and even used by such great luthiers as Del Pilar, Rubio, Papazian, Van Lennep and Gurian. The Professional Series have been the preferred strings by a whole generation of great artists including:

Laurindo Almeida, Julian Beam, Mario Escudero, Maria Luisa Anido, Sabicas & Rey de la Torre

The Professional Series strings are still the standard for excellence expected by all serious guitarists. No single set of strings can possibly bring out the finest qualities of every type of guitar or best suit the varied technique and styles of every guitarist. This product line offers some distinctive designs to perfectly satisfy the demands of professional concert performers.

The 500P Recording Concert set is constructed with clear high-density nylon trebles and smooth tarnish proof wound basses. Also improved, this set has a little more tension than the 413P Studio set.