Missing overtone

[Wailin']

My progress with overtones have been fruitful. The 1st octave and 5th of Bb, B, C and C# come out clearly. However, the next octave Bb2 seems impossible. Yet I'm hitting the next overtone above it. What should I be doing to get that Bb2 to speak?

[MojoBari]

This can be tough. Try fingering a normal Bb2 then quickly switch to a low Bb fingering with the octave key pressed to get the same Bb2. Once you do get it, your brain needs to create a memory of all your oral cavity positions so you can come back to it.

[werkinsnake]

Sometimes the missing overtone is due to a horn that is out of adjustment. I can hit all of the overtones from Low Bb-Low C# on my CONN, but whenever I try to do it on my Armstrong (the beater of the two horns), I can only get to second octaves 5th. Go over your horn with a leaklight and check all of the pads. Key heights also play a vital role.