Compare your ability to ``buzz'' your lips at various frequencies without a mouthpiece, with a mouthpiece alone, and with a mouthpiece attached to the instrument.
Without moving the trombone slide, play various horn partials ... note the adjustments that are necessary to change from one partial to another.
While playing a stable note, move the slide without adjusting your lips.
Play clarinet mouthpiece/PVC tube combination. Experiment with the ``register hole''. If possible, attach a funnel to the PVC tube end and compare the quality of the radiated sound to that without the funnel.
Attach the clarinet mouthpiece to its body and experiment with the toneholes. Notice the affect of closing holes well below and in the vicinity of the most upstream open hole.
Experiment with changing the various excitation parameters: jet length, jet velocity, lip opening.