Search the Community

Wondering if concertina repairers ever resort to pressure testing the seating of pads? Pad seating is critical in flutes, but it's pretty easy to do a suck test, so most flute repairers just do that. Being somewhat of a fetishist, I use a Magnahelic Flute Leakage meter to refine that test. The Magnahelic is essentially a combination of a small air pressure generator (an aquarium pump in reality), a regulator to reduce the pressure further, and a Magnahelic differential pressure meter, which is what gives the unit its name. The Magnahelic is set up to read 8 with the end of the tube open, and ideally should register 0 when the end of the tube is closed. In a whole flute, it's OK to be as bad as 2, but any worse that that is likely to weaken the response. Obviously each pad individually has to be a lot better than 2 if that is to be the whole flute result. The meter is sensitive enough to detect airflow through the whorls of one's fingerprint - you need to wet your fingers before testing a keyless flute. I tried out the Magnahelic on the pads of the concertina I'm looking at at the moment, and found most pads registered around 4. One was much better at around 2, some worse around 6. One even scored an 8 - when I opened the pad, I could see that the seat impression ran right up to the edge of the pad at one point. Enough flow to startle the Magnahelic, but obviously not enough to make the reed vibrate. Now that's possibly not a problem for a high pressure, low flow instrument like the concertina, although it would spell doom for the high flow, low pressure flute. I haven't tried it out on other concertinas, and wondered if anyone has had experience here? Is it just a point of interest, with no practical import? Or should one get obsessive and use such tools in the search for perfection? Terry