CLAVIERS BAROQUES -- how to determine the proper replacement wire for the broken string on your harpsichord or clavichord

Method 1 -- The most reliable guide to the correct replacement wire for a broken string is the broken string. There are exceptions, of course, but in general, if the one that was there sounded OK until it broke, another of the same sort will do as a replacement. What sort was the original string?

• material -- soft iron, yellow brass and red brass are the most usual materials for harpsichord and clavichord wire. Italian harpsichords will typically be strung all in yellow brass, French and Flemish doubles will typically have soft iron in the treble and higher mid-range, going to yellow brass in the bass and red brass in the very lowest bass. Revival instruments may be strung all or partially in steel wire, but steel wire rarely breaks (although it does go black). Early historical copies, those from the 60's and 70's, often have phosphor bronze wire, which goes a distinctive reddish-purple with age. It is not much used anymore, as the tone goes dull in a year or two. If you are replacing a phosphor bronze string you will probably want to use yellow or red brass. You may find the tone so much better that you will want to replace all your phosphor bronze, but I digress. Some harpsichords and clavichords have overwound strings in the bass. If you are like most people, you will not have a metallurgical lab handy, but you can tell a lot by the colour and behaviour of the wire.
• size -- you will need to know the diameter of the wire you are replacing. On stringed instruments, wire diameters are smallest in the treble, expect sizes like .0085" or .009" at the top, and get larger toward the bass, where you may find sizes like .016" and larger, up to .025" or even larger. A micrometer is the only accurate way to measure the diameter. Old wire, especially brass, will probably have stretched a bit, so it may be slightly smaller than when it was new. If you do not have a micrometer, try to get a sample to your wire supplier.
• loop -- the strings of most harpsichords and clavichords and their cousins are attached at the hitchpin by means of a loop. A few instruments have one wire serving two notes as modern pianos do, in which cast there is no loop, the wire is attached to two adjacent tuning pins at the near and runs around a hitchpin at the far end. You can buy ready looped wire or buy lengths of plain wire and make your own loops.
• length -- the replacement wire should reach from the hitchpin to the tuning pin plus enough extra to wind a substantial coil on the tuning pin, an additional 12" is usually lots.

Method 2 -- the other fairly reliable guide to correct replacement wire is the stringing schedule for your instrument. It will give you material and diameter of the wire used for every note on your instrument, although usually not the length, you will have to measure that. It is worth observing that builders are constantly revising stringing schedules, they are not so much analyses as recipes. A good builder, like a good cook, will use the schedule as a starting point but will make his final choice of wire based on what his ears tell him. If you do not have a stringing schedule for your instrument, one for a similar instrument will still be useful as a guide, check out our library of stringing schedules.

Do you have a specific question? Perhaps we can help via a phone call or private e-mail, feel free to contact us.

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