|Acoustics of the saxophone
Bb tenor saxophone
Notes are the written pitch.
At frequencies below about 1 kHz, this curve looks rather like that for G4 and G#4, but raised in frequency. At higher frequencies, however, the situation is complicated by the cut-off frequency. Here, the 1 kHz cutoff weakens the third peak. The first peak can be reduced in magnitude and shifted in frequency using a register hole (operated by the octave key): see A5.
For general comments about the first register, see A#3. Compare with the impedance spectrum for a soprano sax on written A4: same fingering but sounding one octave higher.
For general comments about the sound spectra of the first register, see A#3, which is the first note of that register.
Sound spectrum of a Bb tenor saxophone played using fingering for A4.
For more explanation, see Introduction to saxophone acoustics.
You can hear A4 played.