Who'd have thought… (Squealing drones)

[Klondike Waldo]

OK, I have some results:
I blew up the pipes in question without any bag cover and with f five different bag cover configurations. Believe it or not, the size of the bag cover DID make a difference in how the drones behaved. This particular ( unknown maker) synthetic bag is somewhat elastic, unlike hide or Goretex.


Measurements are across the bag or cover lying flat= (roughly half the circumference ) at the following points: at the neck ( Chanter stock,) just in front of teh blowstick, just in front of the drones, at the belly(widest part of the bag) and at teh breech (opening at the back of the bag cover)
Results of testing:
Does the fit of a bag cover have an effect on spike-ins and cut-off on a synthetic pipe bag?

#0 None Synthetic bag White, no markings;
Strike In Poor:: Squeal, Cut-Off Trailing Drones
at neck 3” before Blow Stick: 4”; Before drones: 8“; Belly: 10 ¼" Breech, N?A

#1 Burgundy velour, Velcro , snug fit: Strike-in Solid; clean cut- off
Neck 3”; before Blowstick; 4 ½"“; Before drones:71⁄2“,Belly:10 “; Breech: 6 ½"”

#2 Light tartan (Cameron) Strike-in:Squealing drones; Cut-off: trailing drones
Neck:3”, Before blowstick:4 1⁄2”, Before drones:10”; Belly:12”, Breech: 7“

#3 Light weight tartan (Cameron of Erracht)
Strike-in:Squealing drones; Cut-off:trailing drones
Neck:3 1⁄2”; Before blowstick: 4 ½";before drones;9”;Belly:11”; Breech; 7"

#4 Burgundy velour ( polyester) zipper
Strike-in: squeal then settled in; clean cut- off
neck:3” before Blowstick:4 1⁄2”; Before drones:8”; Belly:10”; Breech:6”

#5 Black Corduroy ( Before alteration)
Strike in:Squealing drones; Cut-off: trailing drones;
Neck: 3 ¼”; Before blowstick: 9”;Before drones: 12" Belly: 13 ½ "; breech: 9"

#5 Black Corduroy (after alteration)
Strike in:Solid;clean cut- off
Neck:3”; before Blowstick4 1⁄2”; Before drones:71⁄2“; Belly:10"; Breech:6”

Note that Bag # 5 was altered to the same dimensions as # 1, resulting in solid strike-in and clean cut-off. I would not have believed this had I not experienced it and verifed it by experimenting.

Conclusion: with this particular synthetic bag, bag cover dimensions do impact sound quality- strike-ins and cut-offs The significant measurements appear to be the depth before the drones and the “belly”, the widest part of the bag.

[Doug Walton]

Maybe you should throw that bag in the trash.

[Chris C.]

Hey, the bag was cheap and gets the job done, just use the right cover and you're set.

Interesting subject here. Shows how much each part of the instrument makes up the whole.

[Klondike Waldo]

Originally Posted by Doug Walton

Maybe you should throw that bag in the trash.

Thank you for your always constructive posts. I might just do that.
…But in the meantime, there's some research done into what the actual fault was and how to avoid it in future (besides, of course, not buying that type of bag)

In the end, bag elasticity is a factor I had not considered before. When I get around to repacing the bag for this beater set, it will get a hide bag.

[piper_hm]

Originally Posted by In the end, bag[I

elasticity[/I] is a factor I had not considered before. When I get around to replacing the bag for this beater set, it will get a hide bag.

Sounds like it's more a drone reed calibration issue more than anything. Adjustments have to be made depending on how the bag fits, where you're striking in and chanter reed strength.

[Klondike Waldo]

Originally Posted by piper_hm

Sounds like it's more a drone reed calibration issue more than anything. Adjustments have to be made depending on how the bag fits, where you're striking in and chanter reed strength.

Same drones,same chanter, same reeds same piper, same strike-in, same cut-off, same Tune . The only variable in the experiment was the bag cover. I get it that you don't believe it, but that's what I found.

If you have a hide bag you'd like to trade for this mystery marshmallow bag so you can prove me wrong, I'll be glad to oblige

[jackhawkpiper97]

Bag covers can be too small for the bag, but generally it's immediately noticeable when you are putting the cover on in the first place. Your bag should have a strict and distinct max volume, and the cover should fit solidly against the bag when it is at that volume.
Jack

[Klondike Waldo]

Originally Posted by jackhawkpiper97

Bag covers can be too small for the bag, but generally it's immediately noticeable when you are putting the cover on in the first place. Your bag should have a strict and distinct max volume, and the cover should fit solidly against the bag when it is at that volume.
Jack

Yes, but note that the problems with this particular bag occurred with bags that were too big. That bag is too elastic for easy control without a snug bag cover. ( I have a hide bag on the way)