Phase Locking of Drone Reeds in Hollow Mainstocks

[An Draighean]

When I tune my drones, I normally tune the baritone first to the chanter, and then the bass to the baritone, the tenor to the baritone, and finally the tenor against the bass, with a goal of zero detection of beat frequency. Is this incorrect?

I'm not qualified to say what is correct, but I first tune the tenor drone so that it sounds "good" against all notes in the chanter, usually starting with "A". Then I tune the bass drone to the tenor, to get zero detection of beat frequency, then the same with the baritone against the tenor. I will try it your way though, and see if I like it any better.

[Calum]

A piano is stretched because a metal wire is not perfectly in tune with itself; that is the harmonics are not where they should be. It's not a mysterious psychological effect.

[Juan Pablo Plata]

It has been quite a while, but I think this excellent video clarifies the subject. Nate Banton is a forum member, too.

https://www.youtube.com/watch?v=r1SR7r34kZM

[ausdag]

You don't need a hollow stock to experience phase locking. When I brought up the subject on Facebook, regarding a phase-locking-related phenomenon in my set (solid stock), a couple of other pipe makers with experience making both types stated they experienced better phase locking in solid stocks than in hollow stocks.

[elbowmusic]

Funny to find a video I made about smallpipes showing up here. I'm glad it was interesting to folks.

Phase locking is virtually unheard of in the smallpipes an Border pipes world. The typical way that drone stocks and drone bores are designed make it very unlikely there would be any phase locking, so when we stumbled upon it when making drone stocks with shut off keys I was amazed. I had heard of the phenomenon, but did not believe in it. My partner noticed it first and I did not believe him. Eventually though I couldn't deny it was happening. When I became a believer I got a bit obsessed with it and set out to figure out why it was happening. Since we went from zero phase locking to some, I had a place to start and a direction to proceed and I ran with it.

The long and short of it is that, with well designed drone reeds, if there is a space that the drone reeds share that is well connected, and is open to the bag with a small enough hole/aperture then you get phase locking. You can get this with a hollow stock, but you can also get it with a solid stock. The trick is that the reeds don't need to be line of sight connected. They just need to be in a connected space(s). The way that many solid stocks are connected is enough.

One of the helpful factors to experiment with is the volume of air that is within the stock. This is why a solid stock can, under the right conditions, exhibit better phase locking. We've found there's a sweet spot for volume. Too much reduces the effects of phase locking. I call my current design "seimi-hollow".

[ausdag]

Hi Nate,

are you using cane or composite reeds in the video?

[elbowmusic]

Hi Ausdag,

In the video they are composite. Metal bodies with carbon fiber tongues. We noticed it first with cane and/or hydrangea reeds. I worked hard to redesign my composite reeds so they would exhibit the same phase locking properties.

[ausdag]

Thanks Nate. I first noticed phase locking after I had modified various aspects of the innards of my solid stock. Cane reeds. But not to the degree of locking you show in the video. That's a very nice sounding set you have there..

[elbowmusic]

Thanks David. I've worked hard on it. And it's nice when that pays off!

I've made some uilleann drones as well. When I make another my next set maybe I'll make a video of the phase locking I'm getting with those too.