When jumping from a note with a looser embouchure to one with a tighter embouchure I find that I often jump to the wrong note. When jumping from the F just below the bass clef to the F in the bass clef the latter often plays D and occasionally the G or Ab just above higher F. I would appreciated any exercises I could do to fix this problem.

Mixed Intervals exercise from the Arbans (which is just the 5th of the key you are in then use that as a pedal and play up the major scale and you play the pedal every 2nd note).

also practice playing low, pick a study or etude and attempt to play it an octave both higher and lower than written.

also remember firm corners when playing tuba.

TubaChick.