Drone Reed Stability by Chris Apps
Some pipers experience problems getting drone reeds to lock in and stay in tune with the chanter. Drones may seem to be perfectly in tune but when you start to play they move around causing dis-harmony. Here's a few pointers to help ensure your drones not only lock in tune but stay in tune.
1. Ensure that there is a good seal between the tuning pin and the upper section of the drone body. The hemped joint on the pin must be tightly and evenly wrapped to ensure maximum contact between the pin and the joint so that no air can move between the two surfaces. Even the slightest gap can cause instability.
The joint must be tight enough so there is no chance of the drone moving down on the pin whilst playing. However, it must not be so tight that it is hard to move when tuning or that moving it will cause the lower drone reed section to turn in the stock. Do ensure that the stock tenon is hemped a little tighter than the tuning pin. Not so tight that is can swell up and stick or cause a split stock.
2. Seat the drone reeds firmly in the reed seats. The same principle applies here as with the drone pin. Ensure maximum contact between the reed tenon and the reed seat so that no air can leak between the two. Any air leaking here will cause a great deal of instability. Achieving a strong bond between reed and drone will also provide maximum brightness and ring because there is no dampening effect from a loose joint.
3. Set the strength of the reeds so they are taking as little air as possible without stopping. Any reed that is taking too much air will cause the pipe to be hard to blow, inefficient and probably too loud to achieve a proper balance between drones and chanter. It will also make it harder to tune the drones properly and maintain a steady sound.
4. Move whichever tuning mechanism your reeds have so that when in tune with the chanter there is some hemp showing on the tuning pins of the tenor drones. This can be done by either using a tuner to set the pitch to the note of the chanter or when playing them against the chanter in the pipes. The bass tuning height is not as critical but a good rule of thumb is to give the lower pin a gap of around two fingers between mount and ferrule and have the upper pin showing some hemp.
5. When all of the above is done test for stability. The pitch of the drones should not vary with pressure changes. The best way to test for this is to blow each reed without the pipe. Blow to the approximate pressure the reed will be playing once in the pipe and then vary the pressure. There should be no discernible change in pitch. If there is, it will be impossible to get the drones to lock in to the chanter and stay locked in. If you do hear changes in pitch here's what to do.
Ensure that your bridle is set at ninety degrees to the reed blade. If it isn't, adjust it until it is and re-test. Hopefully this will have fixed it and you are now getting and nice steady pitch with pressure changes.If the bridle is at ninety degrees and the pitch is moving then make a very small change to the position of the bridle and re-test. This may be all it needs. If it doesn't work repeat and re-test until it does.
If you have no luck after going through all of these stages it may be time for a new reed(s)
6. Play the drones in the pipe without the chanter. Get them in tune at playing pressure. Now vary the pressure again. If all has gone well you should not hear any change in pitch.
Also available as a YouTube video