(I've got this memory of someone (possibly here, possibly it was Adler) talking about Strauss writing for horns in Db major, a crook that doesn't exist, because the transposition is bread and butter for a horn player but reading an F part with tons of flats is a nightmare.)
It could have been at the request of the horn soloist he was writing for I suppose. So possibly it's whether your horn players are retro or not (got any pictures of retro horn players?)

That indeed was Strauss's strategy once upon a time - the idea that it's easier to transpose parts with as few accidentals as possible, so use a corresponding transposition - and later on, probably as a result of F parts by then being so normal for everyone, he changed his practice. Similarly for clarinets I think - earlier on he wrote for Bb and A clarinets, even together, later when things were moving in the direction of one instrument being used for everything he wrote everything for Bb and let the player sort it out. (The clarinet part in the oboe concerto is a knucklebuster on the Bb as written; he probably expected the player either to play it as written if that's what they did for other repertoire or to play it on the A if not.)

Damn. A perfectly reasonable reason. At least if one assumes he was thinking of the soloist at the time of the first concerto being more up with the latest practice (or more used to playing solos and thus not necessarily someone for whom transposition is their bread and butter) and the soloist at the time of the second concerto being more used to the Mozartian repertoire which Strauss was by then compositionally emulating a bit anyway; while the orchestral horns would correspondingly conform to orchestral practice.

...er, and I've never thought of the first few pedal notes of the tenor trombone being anything other than very solid and stable (snarling yes, imprecise, certainly not); debatably more so than if a special and unfamiliar instrument were to be brought into play for the purpose. Don't forget that Berlioz uses them in the Symphonie Fantastique very audaciously from the point of view of orchestration but very pragmatically from the point of view of playing technique. The pedal notes are nearly all in 1st position; where the A appears (the only other note), only twice, it's slurred (which perhaps means even slid although I've never heard a performance make much of that and I wouldn't want to hear too often one that made too much of it...) from the Bb. Not just effective but very carefully thought out.

Even in the Hostias of the Requiem (possibly one of the most daring bits of orchestration by anyone, ever) he starts the pedals on the Bb, only bringing in the A and G# by chromatic descent. He could hardly have made it easier.

I guess that if you know the right kind of person, any kind of crook would be available. There's a horn in Db solo in Bellini's La Somnambula . . .

And here's an old player . . .

Another favourite low note I forgot to mention was that which starts the Ring.

When Wagner's death was announced, Strauss senior was the only member of his orchestra who refused to stand up as a mark of respect.

I wondered if anyone still remembered that...

I was quite unprepared for how long that pole would have to be just to get two more little semitones. It also had a slightly lubricious curve to it. I think it's still hanging around at my parents' place somewhere...

I should be able to fake that note on the bass chalumeau. That goes to a notated Bb at 415 and I think an extra semitone of lipping might be a possibility...

Favourite horn low notes? Mahler 6, all 8 horns in unison on a low concert A. Usually the second pedal on the Bb side, but I wonder how someone without a double horn would have played it? Were double horns already all the go by then? If not they would have had to lip it from the whole-tone above - if I'm ever lucky enough to experience some period-instrument Mahler I want to hear 8 horns all trying their darndest to get that in tune and damn nearly making it but not quite.

One would think it would go down an octave (the wavelength double)...

open pipe:


closed pipe:


Going to F means its wavelength isn't doubling but increasing by half.  This confuses me.

I don't think what's happening is something with a very obvious explanation. Just tried it with two plastic school descants, an OK garklein and an OK treble. (Not all at once.)

They all gave quiet multiphonics. In no case did I get a lower note on its own except if I blew very softly - any lower note at all only came with a certain amount of overblowing, otherwise they all tipped up to higher overtones (of something!). The descants (normal lowest note c'') gave an e' and a g''#. The garklein (normal lowest note c''') gave an e''b and an a'''b. The treble (normal lowest note f') gave a bb and a d'.

I also have a sopranino, a tenor and a bass lying about. Further examinations on request.