I just got a harpist’s old stash of strings and there are many bass wires. I’m thinking at least three sets if not more. I know that used bass wires go bad and you lose the best resonance that comes with a fresh set, but… What about if they were never strung on a harp and are still in a package maybe 30 years old? Essentially, what is the shelf-life of bass wires? Some are silver/copper and some are tarnish resistant.
They’re certainly less good than new ones, but not as bad as ones that have been played for 30 years. There is not an “expiration date”. Lots of people play with 30 year old wires and are happy. Harpists who want everything the best it can be change every 1-2 years. You can get some idea from the brightness of the color, particularly on the silver/copper ones.