The instrument has a 45 note range, C/E to c’”, and is at 4’ pitch. It is the smallest of the keyboard instruments at normal pitch. Many examples survive from the 16th century before the words spinet or virginal became clearly differentiated. This instrument once had pull-down pedals, C/E to d, in the bass. The pedals in the view that comes with the plan are adapted from an example existing in the Valdrigi collection in the civic museum in Modena. This instrument could be the same one as was listed in the Kraus collection in Florence in 1901. The outer case was sold separately in the 1950s. The instrument was crudely repaired, likely in Italy; later the keyboard was replaced with one of English workmanship. The instrument was imported by J. Solomon about 1952. The 1973 rebuild replaced the earlier repairs of wormy poplar with cupressus sempervirens.

Four instruments bearing signatures or attributions of Joannes de Perticis are known to exist physically at present. W. Thoene (Die Musik in Geschichte und Gegenwart, Baerenreiter, Kassel 1962) lists seven instruments; three instruments come from two catalogs of the notorious faker, Leopoldo Franciolini of Florence (two harpsichords, one spinet, all with 1672 dates). The instrument of 1672 in the Gemeente Museum in the Hague contains crude repairs typical of Franciolini. Furthermore, the 1681 instrument in this brochure was illustrated in a Franciolini catalog (E. Ripin 1974). The instrument of 1683 in the collection of the University of Karl Marx in Leipzig is known to contain much 19th century rework.