Hi @bennie1, when I mention preset volume, I mean the amount of compression behind the tongue for an instant release.

The tongue is stopping the air from coming out (see pu-lip-ku-kmt-tu and aRRRRticulation), the SHAPE is already set and the volume is determined by the abdominal support used.

That being said, if you were to SING a full, rich, resonant note, you will realise there is less abdominal activation required than you imagine and that goes for playing the trumpet too.

If the lips are responsive and dont grip thus impeding the air, you can play a loud upper register note with less work than you think.

Cheers, Greg