If you haven't got a maker's stringing list, here is a
Suggested stringing list for Double Manual Harpsichord up to 2.3m long
and Single Manual Harpsichord up to 2.15m long
.21mm iron (0.008 inch) 8' g2-top 4' d2-top 0.9m long
.23mm iron (0.009 inch) 8' a#-f#2 4' e1-c#2 1.1m long
.25mm iron (0.010 inch) 8' d#1-a1 4' g-d#1 1.3m long
.27mm iron (0.011 inch) 8' a-d1 4' c-f# 1.8m long
.30mm iron (0.012 inch) 8' e-g# 4' G#-B 2m long
.33mm iron (0.013 inch) 8' c-d# 4' F#-G 2.1m long
.36mm brass (0.014 inch) 8' A-B 4' D#-F 2.1m long
.40mm brass (0.016 inch) 8' F#-G# 4' C-D 2.1m long
.44mm brass (0.017 inch) 8' D#-F 4'AA-BB 2.1m long
.48mm brass (0.018 inch) 8' C#-D 4' GG-GG# 2.1m long
.52mm brass (0.020 inch) 8' BB-C 2.1m long
.56mm brass (0.022 inch) 8' AA-AA# 2.1m long
.60mm brass (0.024 inch) 8' GG-GG# 2.1m long
Note: you can also replace strings with the wire one gauge thinner than specified.
Stringing for guidance only. Some instruments should be strung one gauge thinner throughout. Italian Harpsichords are often strung in brass wire throughout.