...There don't seem to be any "historically ignorant performance" recordings on period instruments, though.
No, but there surely are some banal performances on period instruments. This is where Pabloie and I agree most strongly: It's an exception to the rule when being performed on period instruments with historically informed performance results in musical expression with more lasting value than a mere curiosity. And the more the "historically performed" aspect dominates the descriptions and packaging, the worse it's likely to be.
It's fun in some dimensions, simply because all research and learning is fun. But it's not necessarily the listener who benefits. With notable exceptions (whose exceptional notoriety demonstrates the point), the performers who craft real technique on period instruments are likely to be academics more than working full-time professional musicians. Again, note the granted exceptions. But the period-instrument ensemble in any given town isn't likely to have musicians of the caliber of the professional orchestra in that town, even if there is some shared personnel. Even though the musicians in Hogwood's ensemble, for example, are (I'm sure) drawn from the same pool as the other professional orchestras in London, "The Academy of Ancient Music" is a side hustle for most of them, I'd bet. They'd be highly skilled on any instrument, but I'll bet the bulk of their practice and training is using their modern instrument. And the inspiration of the conductor in front of them is similarly not necessarily drawn from the same pool of brilliance. Historically informed music still has to stand on its own as music, no matter what the instruments and performance practice.
While Norrington's star has apparently faded, there were two features of his music that meant more than the instruments used when performing Beethoven: His tempi and his articulation. He followed, wherever possible, the metronome markings (presumably) added by Beethoven. Yes, there is controversy there, but his assumption was to start with those and see where it led. Beethoven's markings went a lot faster than the better-known (i.e., more widely recorded) modern conductors were likely to observe. But even more importantly to my ears, Norrington observed the articulation markings with far more vigor and punctuation than did other modern conductors. (Toscanini excepted to some extent.)
I have been largely content with my classical library for many years, so all my examples are decades old. That's why I bring up Norrington (with Hogwood as the much more widely recorded example confirming my bias), though I could just as easily have brought up Harnoncourt or Trevor Pinnock, who both also managed to put the musicality of the expression first.
Robin has real experience working with groups not of the caliber (perhaps) or fame of the orchestras used by Norrington, Harnoncourt, or Pinnock, so I wonder if his observations match my own.
I've heard some truly superb performances on period instruments, but they always get the "especially considering" qualifier. For example, I heard David Bragunier (RIP), the now-passed tuba player for the National Symphony, perform the Richard Strauss Horn Concerto No. 1 on a turn-of-the-last-century Kruspe Eb tuba. So, we are already on dangerous ground here--a horn concerto being performed on a tuba, an octave down. But that is exactly the sort thing that would have been pretty common back in the 19th Century when solo performers had to show off to audiences just as they do now. He used that Kruspe Eb tuba simply because it was cool to use an instrument from within a couple of decades of when that work was composed, made by a maker whose reputation was strongest in making (French) horns. He was accompanied by the U.S. Army Orchestra, which is certainly a competent ensemble of professional musicians (on modern instruments, of course). The performance was impressive, "especially considering" how hard he was having to work to manage the wonky intonation characteristics of that instrument. Arnold Jacobs made at least as credible a performance, in musical terms, using his enormous York C contrabass tuba at a band camp in Colorado 60-odd years ago. At least he was using the instrument he was most familiar with. Would David have come closer to the fluidity of a modern hornist using his regular modern Eb or F bass tuba? I'd bet a medium-sized Chinese feast that he would have.
(I also heard a performance of what I recall was the Telemann horn concerto performed on natural horn with the Washington Bach Consort at the National Presbyterian Church in Washington maybe a decade back. I suspect the performer was Brad Tatum, and I do recall that the performance was superb, "especially considering" it was performed on a natural horn with a large key-adjustment loop and maybe even a couple of tone holes. Brad Tatum is one of the foremost natural hornists on the planet, but I'd love to have heard him perform the work on a modern horn just for the comparison.)
Which brings me to a point I did not make earlier: Period instruments are more challenging to play well. The standards of sound, projection, and (especially) intonation have improved dramatically over the decades, irrespective of the differences in tone. A professional tuba player (U.S. Army Band career) friend of mine had a side hustle of putting together a quintet of (professional) brass players who were using 19th-Century instruments. His comment: "The first thing you have to give up is the modern notion of good intonation." (He said the same thing about playing in amateur bands after he retired, when he found himself sitting next to people like me.)
We have to remember that listeners are listening with modern ears, ears trained by example to expect modern performance technique. I'm sure I've told the story in this thread: I once played with the Heritage Brass in Dallas, a group that performed at Civil War re-enactments. There was a push to borrow some period instruments from Hill College. I advised against it. I don't think people had any idea how
bad military bands of the Civil War were, but the people we were playing for would be listening to us with Canadian Brass ears.
Rick "probably said all this before, too" Denney