Don’t forget the C Clef, used by the viola and occasionally the cello.
I'd know what the C Clefs are if I saw them, but don't know how it works, except that when I look at two of them (the Alto and Tenor Clef) -- as related to what's written in the Key of C for the Treble Clef -- it looks like the Alto Clef is a major second below the Key of C, and the Tenor Clef is a major 2nd above Middle C such that when the notes are played the pitches will match the other instruments playing from the Treble Clef. (If I'm understanding this correctly.)
So, then, Concert A would be written as a G natural in the Alto Clef but sound as Concert A; and for the Tenor Clef, it would be written as a B natural but sound as Concert A.
Is that right??
...'twas in another century. *sigh*
(Not a total dummy here...in the past I've transposed a Bb instrument (Trumpet) and an Alto Sax (Eb instrument) for use in performance. I just had to remember either down a whole step/major 2nd (trumpet), or up 3 half steps/minor 3rd (sax) to find the key to use in the transposition.
I cannot tell you how much I am enjoying your question. It made me run to my out-of-tune clunker piano for a quick refresher and in the process reminded me of how very much I miss music. I went away from it a long time ago, but the love of music will always be there.