While this site concentrates primarily on acoustical instruments, occasionally there are some “virtual” ones which are a bit fascinating. This one is called UNA CORDA by Native Instruments. It’s included here because it is based on a real instrument that has only a single-string per key.
UNA CORDA is based on a physical instrument. The original 64-key upright piano was conceived and handcrafted by innovative piano builder David Klavins, and developed in collaboration with musician, composer, and producer Nils Frahm. The piano is unusual in that it has just one string per key – standard pianos have up to three strings per key. Klavins designed the piano with an open frame and a thin, ribless soundboard to produce a highly resonant tone. Frahm added fabric preparations, placing cotton, felt, and other fabrics between the hammers and strings to alter the attack of sounds. Klavins subsequently built an 88-key version of the piano especially for the Native Instruments sampling session.
UNA CORDA, in its virtual form, is highly versatile, enabling users to create a wide variety of sounds and effects. UNA CORDA offers three sound banks: the pure sound of the original piano plus the piano with cotton and felt preparations. Through a straightforward graphical interface, users can easily sculpt the primary characteristics of the initial sounds, adjust response characteristics, and add an array of vintage effect chains. By manipulating resonance, integrating harmonics and overtones, adding noise and ambience, dialing in reverb, and applying other effects, users can generate truly unique results.
The video provides an even more in-depth at how the all came about.