Car Horn Sound

The ideal shape of a note, and the ideal shape of a phrase are generally the same. The note should begin with immediate resonance and fullness, then naturally sustain and the conclude with a mild taper. If you want a perfect example of this, simply hit a key on a piano and hold it down. You don't even need to worry about the sustain pedal. Listen to the immediacy and squareness of the beginning of the note and the following sustain and taper. I attempt to make most of my phrases mirror this shape. Of course there are exceptions. Some phrases end with a sustained crescendo and there are many special effects that are require of us trombone players. However, the majority of the time (see 99% of Rochut phrases) this is what you are aiming for. 

If you would like a good way to practice this, start with a long tone. Take an easy, full breath and ping the front of the note as though you were hitting a chime. Then simply allow the air in your lungs to empty naturally. Don't artificially sustain the volume by forcing the airstream. Artificial sustaining sounds like someone leaning on a car horn. There's a reason why it is so annoying when someone is leaning on their horn. That's because an artificially sustained sound is NOT pleasing to listen to! When you start to run out of air, simply let it go! This should result in a beautiful, easily produced long tone with a seamless taper at the end. Then use that exact same airstream to play the first phrase of Rochut #2, or any other cantabile phrase for that matter. Sounds kinda nice, right?