I am having trouble playing an octave gliss (middle Ab-Ab)... I have tried the half valve technique but I'm not 100% sure how to actually do it and I don't really seem to be getting anywhere. The notes in between just seem to slot in and it sounds pretty terrible! Does anybody have any clear advice for practicing and technique for doing a gliss such as this? I've never really done them before so it is most likely just my chops not being used to it!
Any advice will be much appreciated! (Please don't just tell me to ask my trumpet tutor or band leader)