How does the musical interval of 9th sound like?

Musical example:
Who Wants to Live Forever - Queen
https://m.youtube.com/watch?v=_Jtpf8N5IDE#fauxfullscreen


The brilliant song is writen in the musical key of E minor. This means all notes are natural or white keys except F which is F sharp.


Naturally the first bass is E. Synth plays the usual 1 3 5 with respect to bass ie E G B (E minor chord) but also plays F ie F sharp creating a ninth interval with respect to bass. Ninth intervals sound great to the human brain as you can tell by listening to the introduction. (The note C is also played on synth while bass is E so there is also the interval of 6th. At the end of intro a 4th ie note A is added).


But another even grater sounding 9th is next created by the Brian May vocal. He sings, "There's no time for us", using the notes:


E(there's) A(No) B(time) C(for) C(us).


As soon as he sings "Time" ie note B bass becomes A creating an amazing sounding 9th interval (with respect to bass). (All music is referenced to bass hence the name bass or base [Bach]. The 3rd with respect to bass ie note C is added [Bach] by the pipe organ so that the interval of 9th sounds amazing to listener's brain [Bach].


How do we find the chord?


Since bass is A using the 1 3 5 (7) (9) rule.


We have:


A bass and A C E


So the complete chord or harmony including the vocal is:


A bass and A C E B


How do we name this chord?


It is easy.


We start with the bassier note ie A [Piston]. We create in our mind or on the piano or keyboard etc the A major scale which is A B #C D E #F #G A.


Note C does not belong to the set of notes of A major scale (it is one semitone less than the A #C ie 3rd major interval) so the interval is a 3rd minor. B belongs to the set of notes of the A major scale so the interval is a 9th major.


So the amazing sounding chord A C E B is called:


A minor 3rd major 9th


References:


Bach Bass Rules - Bach, Niedt - PDF


Harmony - Piston - McGraW Hill