Octave notation puzzle

If I look at the Halion SE screen, it helpfully reminds me that middle C is C3. No surprises there.

What I do find a bit puzzling is that, if I highlight a note in Write mode, and that note is middle C, the status bar at the bottom of the screen says Note: C4.
Now, I’m fully aware that there are several competing conventions for octave notation, but … I’m puzzled.

Just for the record, this is a bassoon score, no transpositions, conventional or otherwise, apply.

See https://www.steinberg.net/forums/viewtopic.php?p=810087#p810087

There has never been an official MIDI standard for note names - though of course middle C is always MIDI note number 60.

There is an international (ISO) standard for musical pitch names, which makes C4 = middle C, but that has the irritating side effect that C0 is MIDI note 12, not MIDI note 0. Some MIDI manufacturers took the logical view that C0 should be MIDI note 0, and therefore middle C was C5, while others wanted to avoid “double digit names” like C10 (which was a rational decision to make with 1980-era electronic display technology in MIDI equipment), and called middle C C3.

The resulting confusion will probably be around till MIDI becomes obsolete!

I was aware that C3 for middle C is widespread in the synthesizer world. I wasn’t aware that some MIDI manufacturers call it C5 and that ISO 16 calls it C4.

About this last I don’t feel too bad. My Harvard Dictionary of Music (1986) mentions the standard only insofar as it says a’ = 440Hz. My Concise Grove (1988) merely sniffs that “several systems have been devised using inferior numerals, with middle C as C4”. And the big Grove seems to ignore ISO 16 entirely, other than to dismiss a’ = 440Hz as “artificial and unrealistic”.

I still think it is weird that two intercommunicating programs from the same stable and forming part of the same distribution call the same note by different names.

Maybe “MIDI (hardware) manufacturers” was a bit of brain fade, but there was and still is plenty of MIDI software that labeled MIDI note 0 = C0, and therefore middle C = C5. Sonar and its predecessors, for example.

Standards are very important in computing. That’s why there are so many different and incompatible ones.

If I’ve got my maths right, then surely using C3 means that MIDI 0 is C minus 2…?

Correct, but most MIDI users wouldn’t go more than 3 octaves below middle C anyway. A piano only has 3 more notes below that, and most MIDI keyboards (except specialist piano keyboards meant for playing live) have notes from C to C.

A few pipe organs do go down to the pitch of midi note 0 with 64-foot stops, but the written compass of the pedal board only goes down 2 octaves below middle C and a 64-foot stop plays three octaves below written pitch.

As I mentioned in my linked post, there is a convoluted history. Music notation applications (and MusicXML) have more followed the C4 convention. Sample library makers have followed the other. Whichever standard we pick is going to be inconvenient for someone.