The last time your clarinet (or your student’s clarinet) was played things seemed to be functioning well, but now it mysteriously stops working entirely. What’s the cause? Here are two easy ways to determine the problem:
1. Do a visual inspection. Is the reed in good condition and aligned properly? Are there any pads missing? Are there any obviously bent keys? Has a tenon cork (particularly mouthpiece or barrel) disintegrated? If not …
2. Do a pressure test. If the barrel-to-upper joint tenon cork appears intact, clean the barrel with sanitizing spray, then cover all open tone-holes and the bottom of the bore with your fingers as shown in the illustration below. After sealing the barrel against your lips, blow firmly into the bore and see if it holds pressure.
If the top joint does not hold pressure and nothing is obviously damaged, a common issue is that the A to A♭ adjuster screw (shown in the illustration below) may be out of adjustment:
When the A key is pressed, there should be a tiny bit of motion before the A key touches the tip of the screw and begins to lift the A♭ key. This ensures that the A♭ pad is allowed to sit firmly and seal securely against the tone-hole. Sometimes the A pad will swell slightly, raising the position of the A key and eliminating the needed free play. Another possible cause is that a student may have adjusted the screw and turned it too far clockwise. Sometimes the adjustment is off so slightly that the clarinet even passes the pressure test described above. Either way, the solution is simple: Turn the screw counterclockwise 1/8th of a turn and recheck for free play between the A key and the screw tip. Repeat as necessary until a small amount of clearance is achieved.
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