|Acoustics of the saxophone
Bb tenor saxophone
Notes are the written pitch.
This is the seventh note in the altissimo or very high range, and plays at the third peak. The weakness of peaks in this range (due to the relatively large cone angle of the saxophone) explains why notes in this range are hard to play and require the player to assist the weak impedance peak of the bore with a strong impedance peak of the vocal tract. See this page for an explanation and some interesting results.
This sound spectrum includes transient excitation from the beginning of the note, and so has traces of a subharmonic being excited above 5 kHz.
Sound spectrum of a Bb tenor saxophone played using fingering for C#7.
For more explanation, see Introduction to saxophone acoustics.
You can hear C#7 played.