Up to the middle of the 20th century, the only available strings for guitar were plain gut for trebles and silk wound strings for basses: their acoustical performance was quite different from that of modern stringings.
The salient characteristics were: a marked tonal presence, a response and brightness typical of gut strings (certainly superior to plain nylon and in some respects closer to fluocarbon strings) while, on the other hand, basses had an exquisitely vocal quality, i.e. not so bright as, and with less sustain than modern wound on nylon strings, with a sound that was richer in fundamental frequencies.

Our Ambra 900 set was developed keeping in mind this historical fact, in order to best re-create, by means of modern synthetic materials, the sound of gut and silk-wound basses of that times.

This set was conceived for one grade of tension only, and consists of gut-coloured Supernylgut® trebles, with a rectified surface exactly as it’s made on gut strings, adopting the representative mean diameters as indicated by Pujol in his method “Escuela Razonada de la Guitarra” of 1934. Basses have a silver-plated copper winding over special multifilament core, that we call ‘Rayon’, and are specifically balanced between metal and core in order to achieve the same texture of sound found in the original silk-wound strings.