“Restoration” , as we’ll use it in this text, refers to the act of bringing a stringed instrument as close as possible to new condition using as much of the original material as is feasible.
A full restoration normally results in all of the repairs being made invisible (a very time-consuming and expensive process), and having the original varnish looking as unblemished as possible. Missing exterior wood is in some instances replaced with wood removed from the inside of the instrument, or if that is not possible, replaced with wood of the same age, from the same geographical area, and visually similar if not nearly identical.
Full restorations incorporating the above are usually reserved for important Italian instruments, and undertaken only by the handful of luthiers qualified to do them.
Restorations, however do not have to this extensive, and in fact can encompass only what makes sense for the instrument and its owner. A few years ago it didn’t make a great deal of sense to restore, or in some cases even repair, 100 year-old German commercial instruments. Now that they have become scarce, and in many cases their old sound more mature and desirable than anything new, their current value suggests that it may make sense to consider at least a partial restoration.
Here are a couple examples. A cello was sent to us from the Midwest: a nice maker-instrument from early 1900’s Germany, purchased at a good price from a reputable auction. Excessive use of dampits (read the Cello Chatter on humidifying your instrument) caused extensive warping and even rotting damage in the lower bout area near the endpin, and invited a colony of woodworms to take residence there. The worms gradually ate most of the wood between the varnish and the inside of the rib area near the endpin, leaving almost no structure to the wood. Any small trauma, like a bump or even a tap, caused cracks and just general collapse. Outside this area however, the cello was in very nice condition.
We removed the part of the two lower bout ribs that could not be repaired, grafted new (actually old but solid) wood onto the good part of these ribs, varnished to match (the splice was almost unnoticeable), did a few other repairs and the cello was in great condition. Even with the cost of the repairs and the cost of the cello at the auction, the Midwest customer paid far less than the cello was worth when it was done.
What about an older cello whose accepted monetary value in repaired condition (remember that great sound has little to do with a cello’s net worth) is, let’s say $3500. You paid $3000 for it, the neck is loose and needs to be reset, there are some cracks in the ribs where your 8 year-old brother (or son) inadvertently dropped a baseball on it, and you’ve noticed another crack in the top because you thought that you really didn’t need to humidify the cello’s living space this winter. Your luthier said that it would cost about $1000 to fix what ails it, and you would then have more into it than it is worth. But you love the sound: in fact you played some new cellos in the local shop and you hated all of them, and they cost $4000 - $7000.
My thought is that if you have an older instrument that works for you, it makes sense to consider repairing and/or restoring it as long as it doesn’t outlandishly exceed its current appraisal. As shop owners, we would make far more money selling you a new $4000 cello than we would restoring yours. But old sound is lovely and increasingly hard to come by. And instruments with properly-done repairs play as well as those without repairs at all. They just aren’t worth as much.
Other than the restoration cost grossly exceeding the instrument’s value, when is it not a good idea to restore a cello? Recently we were offered a German cello from the 1920’s. It was in decent condition, although it began life on the other side of the tracks with a thick sprayed varnish (somewhat unusual in my German-commercial experience), and somewhat rough workmanship. It played ok, but what finally held us back was that the top had been regraduated (its thickness reduced), fairly recently judging by the color of the interior wood, to the point where it was simply too thin in critical places. The purpose of regraduation is usually to try to darken the tone but the effects, if the procedure goes too far, are usually temporary if the process works at all. The weakened plate eventually can produce less and less sound, and be vulnerable to cracking and sinking. Instruments sometimes survive excessive thinning, but in our opinion it isn’t worth the risk. And it doesn’t make sense to restore one of these unless it is fairly valuable and worth the high cost of a chest patch which may or may not rescue the tone.
As mentioned, older cellos are not as easy to find as they once were. If you have one, find a luthier you feel good about and discuss it with him/her. It might be worth some work and you might end up with a cello that is not only structurally better and much more pleasing to look at, but one with a sound even nicer than it had.