The entry for harpsichord currently on UMIL is actually a specific harpsichord

[JoyfulGen]

I was intrigued by the fact that the UMIL page for harpsichord doesn't have a French label, and it turns out that's because it's a Wikidata entry for a specific harpsichord, built by a certain Alessandro Trasuntino in Venice in 1531 and now part of the collection of the Royal College of Music. That entry is only in English, because only the RCM cares about it. The Wikidata page for the instrument harpsichord is this one and it has a bajillion language labels, which makes more sense.

If you look up "harpsichord" on wikidata, the first result that comes up is the general page for harpsichord, but the ones right after that are specific instruments from museum collections, like the one that ended up on UMIL.
In fact, the same thing happened with the clavicytherium: this is the instrument on UMIL and this is the general clavicytherium page.

I bring this up because there are a lot or wikidata pages just like this, that have the same name as a general instrument page but are actually a specific instrument, usually a museum piece. This ties in to @kyrieb-ekat and @dchiller's excellent discussion about determining what is and isn't an instrument. At one point does a museum piece become its own instrument?

[kyrieb-ekat]

This is a solid find! There are chunks of clarinet's on there as well that are all unique clarinet entries held by the RCM, and we certainly don't want those; so in this harpsichord example, I don't think we'd want this unique example of a harpsichord built in 1531, we want what it's an instance of—a harpsichord.

For our purposes, I don't think we want instruments unique for their owner or maker, nor instruments found at specific sites or excavations; a bull-headed lyre excavated from the ruins of Sumer would remain an instance of "bull-headed lyre", which we would want in UMIL. If this makes sense? I think a gap for "[PLACE] [Instrument]" would be the only exception to this, because there can be regional variations of instruments that are otherwise instances of a grandparent instrument (as with your discussion about jaw harps in the other issue!!). Thoughts?

[annamorphism]

I think we could say it should be true that every instrument is a "subclass of" something else--the two examples above aren't subclasses, because nothing else could be an instance of the particular harpsichord at the RCM. That doesn't solve every problem, because some things like brands do define a subclass of instruments ("Fender guitars") although we don't want to define them as different instruments...

[annamorphism]

(and speaking of things that might or might not be different instruments in the other direction: there's about a zillion different things called a "rebab", which are not even all the same family of instruments. Even the ones that are broadly speaking "spike fiddles" differ from one another--are they different instruments? e.g. English wikipedia says the Iraqi version is called a joza, but German and French wikipedia think the joza is distinct from a rebab. As far as I can tell (my Arabic is limited to the alphabet) Arabic wikipedia doesn't really mention the joza except to say there are seven shapes of Arabic rebab, though it does have a separate page for the central Asian rebab.)