Everybody was back this morning for round 2 of our flute making class. All had done their homework, that is creating a bird and turning their flutes round. Now we were ready to start the voicing process.
The process to make a Native American Flute sound great is not too complicated, but must be done pretty precisely. All they had to start with was two small holes we had drilled in the blanks to show them where the exit from the slow air chamber (SAC) and the true sound hole (TSH) were and that was it. It was now a process of shaping those holes into rectangular openings with sloping ramps on the underside. The ramp on the TSH is the most critical because this small wedge of wood is what splits the air stream from the SAC and bird and makes all the sound.
Once the rectangular holes were burned, everyone settled down with small rasps and files to make the openings and the ramps perfect.
Once everybody had the holes properly shaped it was time to add the bird and check it out. Many had their flute sounding great right off the bat, but a couple had to either tweak the TSH or their birds. Finally we had everyone’s flute sounding great, so now the question was “what key?”. The bore we routed last week would work for an E, F, F# or G flute.
Most went for an E or F, so we had to cut the bore shorter and shorter on the bandsaw until we got to the right fundamental note.
Now everyone had a good fundamental in the right key. Now came the tricky part of placing the fingerholes. We used a computer program called NAFlutomat to tell us where to place the holes, but rather than drilling them, we burned the holes in using heated steel rods. Once again you had to sneak up on the right size, finally getting the holes big enough that the tuner we were using registered the correct note.
The burning rods were heated with a torch and then pushed/burned through the flute wall.
They started at the bottom hole, tuned it then moved on to the next hole. This style NAF only has five holes, but there was a lot of refinement to get the notes perfectly tuned.
After the five holes were tuned, it was time to play.