Not that I have any problems , but I hear this phenomenon in a lot of pipe recordings and I am just curious. I think it is a unique characteristic that adds to the tone and color of the pipes.
It’s the sound I hear when the drones dip down in pitch (reminiscent of a lawn mower running over thick grass when the sound changes) on certain notes, does any one know why It happens on certain notes? Is it the drones being to open, the reeds to old or are they too stiff?
Ideally the drones shouldn’t move. If they dip down in pitch or rise in pitch it is due to added pressure on the bag affecting a poorly adjusted reed, particularly when playing up in 2nd octave. It is rectifiable generally with a few minor adjustment to the reed.
Most other Bagpipes are played at a constant pressure,because their chanters are not called on to over blow a second octave, thus the drones don’t have to cope with much variance of pressure.
It is always important to play the UP’s with a bag that is not more than 90% full, so that the control of pressure is made with your elbow… a little More/ or Less so as to squeeze the best sounds out of each note of the chanter.
The drones of our instrument are designed to take these pressure variations, both in their bore- to- length ratio and in the reed design… all this ,of course , within limits… The Chanter reed has to be made so as to allow free passage through the upper octave without too much extra pressure.. or , if you like, maybe that should read , Ideal Chanter reeds are those where the range of pressures over the whole gamut are at a minimum.
Sometimes it is more a tonal change in the overall drone sound with changing pressures that one hears, other times it is as Ausdag says.
A phenomenon I have observed very occasionally on the GHB is that when a stand is well tuned and chanter and drones lock together, a slightly out of tune note can pull the entire stand of drones off pitch slightly, giving the effect described. I suspect this would be swamped on the Uilleann pipe by pressure variance but I’m not sure.
Ah! I wondered if the bag might have anything to do with it. I han hear it sometimes on the Fine Art Of piping, and in some of Tommy Recks recordings. But I mostly hear it in Seamus Ennis’ pipes, which were really really leaky…
I can only speak from my very limited experience. I bought a half set from David Daye, who uses synthetic plastic drone reeds. He has a page on his website where he talks about how to adjust the reeds if the pitch is wavering up or down which may be of interest: http://www.daye1.com/reeds/drones/artifdrontip.html
I’ve certainly had some success addressing any stability issues with my by drones adjusting the reeds as he shows in the article, although I probably need to work on them a bit more as they do still rise a tiny bit with pressure.
As an aside, even though the drone reeds are made of plastic, David’s drones have a gorgeous, rich sound.
I am not convinced you are hearing anything different than the voices you mentioned on another thread. I think all you’re hearing is the change in interaction between the notes on the chanter and the drones. The harmonics changing (for want of a better description).
I used to live not too far away from an airport, small planes going overhead a lot of the time. They’d have similar effects, you’d be playing away and all of a sudden your drones seemed to go off completely. Only, they didn’t. It was the sound of a single-engine plane interfering with them. A similar thing can happen when playing the pipes or listening to (a recording of ) a piper, the tune turns a corner and for a moment the drones seem to change completely. Only, they don’t. Not really.
[edited to add a missing word and make slightly more sense]
I believe the truth of what Mr. Gumby is saying can be seen when you examine the sonograph (correct word?) displayed when the recording is examined with Audacity. I believe the ‘beating’ of the drones harmonics against each other create “artifacts” in our binaural hearing system.
Just my two cents worth
Bob
For what it’s worth I believe that Seamus Ennis’ drones actually do go out of tune and start ‘beating’ for example in this recording here http://www.youtube.com/watch?v=aF3fW4Nox9U The same thing happens in the first recording here https://soundcloud.com/gleeson-uilleann-pipes when the chanter goes to the 2nd octave. It has nothing to do with the chanter interacting with the drones, it’s just too much pressure for the drone reeds to handle and stay in tune. What was heard with the plane engines was just their pitch moving in relation to the the pitch of the drones. It’s a different thing, the other one caused by the interaction of another pitch, the other one cased by the actual air pressure driving and determining the pitch of the drones.
Obviously drones can waver at times but as I said, I am not convinced that is what OP is referring to, so I suggested another possibility to consider.
Both Ennis and his Coynes were a bit frayed round the edges by that point in their career. Though I guess old fashioned TV studio lights wouldn’t make things easier either. Lovely performance, for all that.