Many pipers will say, in jest, the best way to use a tuner is to throw it in the trash. The only reason you can do that is because the bagpipe has a built-in tuner—the drones.
My ultimate goal is to show you why the bagpipe chanter has the tuning it does and then how to use a generic (i.e. cheap) tuner to tune your bagpipe chanter. You may already know how to tune your bagpipe chanter with or without a tuner, so what you will get out of this series of posts is how that tuning works on a theoretical level and how it's deeply connected to the drones. This information has many uses that we'll discover as we go along.
The only way to get a perfectly tuned bagpipe is to tune your chanter to the drones. They must be tuned together, playing together, in order to achieve perfect harmony. This is because the drones are the foundation for everything about how a bagpipe sounds and tunes. Almost everything about the tuning of a bagpipe chanter is determined by the drones.
The highland bagpipe chanter has 8 finger holes that allows 9 notes (if you were just to uncover 1 hole at a time, which is sort of what we do). Someone, somewhere, decided that the drones would be tuned to the same note as the second lowest note, that note being 1 octave below the highest note. This decision immediately determines how the other notes on the bagpipe chanter are tuned. All the other notes must harmonize with this constant droning that is tuned in reference to these two notes we named low A and high A, respectively (calling them "A" was seemingly decided upon during the development of staff notation for the highland bagpipe). If it were decided to tune the drones to a different note, like the lowest note, the tuning of all the other notes, and what those other notes actually are, would be very different.
Many will know that the first step in setting a new reed in a bagpipe chanter is to ensure that there is an exact octave between low A and high A, meaning the pitch of high A is exactly twice that of low A when viewed in terms of the frequency of oscillation of the sound waves. Using the drones as a tuner, this is done by comparing both notes to a single drone playing; the idea being that the reed is moved up or down in the chanter's reed seat until the drone doesn't need to be re-tuned for it to be in tune with both of those notes. Thus, we ensure that the drone(s), low A, and high A are all playing the same note, just at different pitch frequencies in different octaves. As an aside, if we set the bass drone pitch equal to the number 1, then the tenors tune one octave above that at a pitch of 1*2 = 2, low A tunes another octave above that at 2*2 = 4, and high A yet another octave above that at 4*2 = 8. Each next octave is obtained by multiplying the previous pitch by 2.
Having established the tuning of 2 notes, the tuning of the other 7 notes needs to be addressed. Having adopted the staff notation used by many other instruments, it makes sense that the bagpipe notes will be given the same names. If we start on the note A, the other notes of the chromatic scale capable of being represented on the staff are: A, Bb, B, C, C#, D, Eb, E, F, F#, G, G#, A, Bb, and so on repetitively through the octaves.
Bb is read as "B-flat" with the symbol ♭. C# is read as "C-sharp" with the symbol ♯. Notes without modifiers are referred to as being "natural". The symbol for natural doesn't have a convenient keyboard equivalent but it looks like this ♮.
I might surmise that these are the notes you get when you roughly equally space the holes on the chanter the best you can. We will actually see later that these are the same notes contained in the harmonic series produced by the drones. Having determined that the second highest note is a G, the last of the 9 notes, the lowest note on the chanter, is therefore also a G, giving low G and high G. This finalizes the bagpipe scale as: low G, low A, B, C#, D E, F#, high G, high A.
Colloquially C# and F# are referred to as just C and F, however it is important to know that to any other musician, saying "C" means C-natural. This is our first application of knowing the theory behind the tuning of the bagpipe chanter: when talking with other musicians about our scale, we need to remember that our C and F are actually C# (C-sharp) and F# (F-sharp). This issue is often compounded when bagpipers write down music and leave off this important information! If omitted, any non-bagpipe musician would immediately assume everything we played was in the key of C-major. The key of C-major would have the following scale: low G, low A, B, C, D, E, F, high G, high A.
This is a problem because the bagpipe scale is actually in the key of D-major! When sheet music is produced it's supposed to indicate what scale, or key, is to be used in the key signature field. But many bagpipe scores omit the key signature entirely under the assumption that only bagpipers will be looking at it, which has the unfortunate consequence of making it look like we play in the key of C-major, which we don't. Look through any bagpipe music books you have and see if any omit the correct key designation (which is D-major):
What this key signature tells the player is that every time the note C is encountered, C-natural should be played if in the key of C and C# should be played if in the key of D; the same is true for F/F#. Bagpipers need to be clear that they are playing C# and F# in the instance that they decide to play music with non-bagpipers.
For a while now, we've lost sight of the drones, the built-in tuner of the bagpipe. In Part 2 of this series, we will see the differences between the creation of the equal temperament scale used by most generic instrument tuners (based on the number 2 we saw earlier when creating octaves) and the just intonation scale used by the bagpipe, enforced by the persistent drone of our, well, drones.