The Scale of The Great Highland Bagpipe and Its Relation To Its Drones

A legato instrument without the ability to play louder or softer, the bagpipe scale is different from other instruments because of its need for consonance with its drones. It is an ensemble instrument. Because the drones depend on unvarying wind pressure, they in turn govern the pipe scale. The low A of the pipe chanter is an octave above the two tenor drones and two octaves above the bass drone. So it may be said that the instrument plays in three octaves. It can readily be seen that any attempt to interfere with the scale of the instrument would simply destroy all its characteristics. It could be said that the pipe scale is a tempered scale. But is it? Perhaps tempered because each note is governed in pitch, according to some other temperament acting upon it and we will come back to this point further on.

The chanter scale consists of eight notes, low A through high A, or one octave. When the chanter is closed, an extra note (low G) is sounded which is actually an extension of one note into a lower octave of the same scale. Therefore, the melodic range of the chanter is an octave and one note. Low A (A major) is the lowest fundamental note. This seems to be the basic finger position of most simple wind instruments. The scale is actually the set intervals (mathematical measurements or ratios) between notes and the amount of intervals determines the pitch of that note. The chanter has one major and four minor tones plus two limmas. These limmas only occur in the intervals between the notes C and D and F and high G. Here is where the problem of describing the chanter scale gets tied up with our old friend temperament and semi tones.

Because the intervals between C and D and F and high G are not in equal proportion to the frequencies of the other notes, they do not produce tones or sounds that are in balance with the rest of the chanter's scale. D is sharp and high G is flat. Here we find temperaments acting against or upon the rest of the chanter scale. Consequently, the Highland Bagpipe scale is mixolydian. We may say that it has a major third and a minor or diminished seventh, which is gapped. But for these, the pipe would have a just scale. This is perhaps what causes the pipe to sound Eastern or oriental to some but it is a very Western scale. Perhaps it may even be said to sound medieval.

The pitch of the Great Highland Bagpipe chanter is B flat against its lowest fundamental or main tonic of low A. Oddly, the extra note, low G, made by closing the chanter, does not tune or harmonize with the drones. It is the most dissonant note of the pipe scale, having no harmonics against the whole. Yet it is constantly in use in Scottish piping to form grace note clusters. Nevertheless, we are still left with the provocative question of where the chanter's scale comes from. A safe guess might be ancient Greece. We know that Ptolemy experimented with the scale of instruments in the second century A D and a striking affinity exists today in the chanter scale of the Macedonian Bagpipe and that of the Great Highland Bagpipe.

The pitch of the two tenor drones is B flat. Their frequency is 240 cycles per second and they sound one octave higher than the bass drone and one octave lower than the pipe chanter. The drones enhance the chanter sound. Poor drones or poorly tuned drones will sap the life from an otherwise good chanter. Indeed, they will cause the instrument to seem louder and force it to become more difficult to play and maintain overall steadiness. When properly in tune, a tenor drone sounds low A. The pitch and harmonics of a drone are affected by the steps or shoulders in its bore. Harmonics are the multiples or extra sounds of the fundamental note being sounded and the over all tuning of the Bagpipe depends entirely on the balance or blend obtained between the fundamentals and harmonics of chanter and drones. Orchestral instruments tend to have rather weak harmonics beyond the tenth or eleventh harmonic. Not so in the Bagpipe. Timbre is a measurement of the strength of a harmonic. High harmonics make the overall sound bright while low harmonics make for an overall dull sound and affect overall amplitude. The internal bores of a drone affect the pitch of the instrument, the wider the bore, the higher the pitch and the greater sonority or timbre of the whole. Narrow bores produce a flatter sound. The use of "tuning straws" in the chanter and drones was an ancient method used by several European piping cultures to balance the top and bottom hands of the chanter notes as well as the drones against the chanter. Because of the previously noted temperaments, one cannot tune a Bagpipe drone alone or by itself. The three drones must sound together with the chanter and are then tuned one by one, locking in their harmonics with those of the chanter. Theoretically, sound waves should travel through the drone unrestricted and undistorted to produce optimum brilliance of tone. The possibility of distortion may occur where the narrow bore of the lower part of the drone (tuning slide) empties into the larger bore of the upper drone and then back into a smaller bore before collecting in an even larger cap or bell at the drone top. Until approximately 1955, sound waves were subjected to distortion at these square cornered air reduction areas in most drones. Today they are more rounded and less abrupt. Drone bores today are often polished to reduce air friction. The trumpet, pear or bottle shaped bells at the drone tops have an important mellowing effect on the overall drone sound. With softer sounding pipes, a single drone is adequate as in the Spanish Bagpipe.

A phenomenon of the tenor drone is that it has a first harmonic so strong that it appears to the ordinary ear to be the actual fundamental note of the drone and causes its pitch to seem an octave higher than it really is. The outermost ends of the drones, the bells, are closed by a flat cap with a hole in the centre. This cap has the effect of smoothing the sound by suppressing the highest harmonics. When a drone is tuned to its maximum length, the sound becomes smoother and the pipe becomes easier to play.

Much thought by the non-performing community has been given to the age of the bass drone and whether or not it predates the tenor drone. A chicken or egg mentality! The bass drone is the key of harmony and balance. It brings out the harmonics in the chanter and provides the framework upon which the sound of the Bagpipe is constructed. It is the most important component of the Bagpipe, actually determining its sound. It is the most difficult drone to reed because there are more joints, different gage bores and bore shoulders to cause sound wave distortion. Because of its length, it has a tendency to warp with age especially in the bottom joint and this will make reeding more difficult. The bass drone is two octaves below the pipe chanter and one octave below the tenor drones. It has a very strong second harmonic, giving it the phenomenon of sounding a fifth harmonic, which it does not have! Of course, it has that extra chamber to add to its resonance. Its keynote of low A is 114 to 120 cycles per second and it can only be used with a conical bored chanter. It is always constructed the same way, as a series of joints and slides for tuning in most European Bagpipes, especially the Italian and Spanish varieties where the relationship of bass to chanter is essentially the same. Its pitch, like the two tenor drones, is B flat and it can be documented to the thirteenth century in Europe. When and how the bass drone came into being is not known but it has a definite musical purpose. A safe guess could be Rome simply because most things of an ingenious nature come from Rome or ancient Italy and it is a curious fact that the drone bores of the Highland pipe are very similar to those of the Italian pipe. The bass drone adds strength, colour, and an overall richer and full sound. Because of the drones length and narrow bore, it produces a strong set of overtones or ghost tones. Ghost tones are heard when played against the chanter on low G, B D F and high G.

We can now begin to understand that drones also govern the scale intervals and are a temperament in themselves upon the scale. If the note intervals of the chanter were changed, there would be a dissonance between the drones and a dissonance between drones and chanter. A rather important purpose of drones is to smooth over the hard edges of the chanter sound. Most ancient writers comment on the loudness of the Bagpipe. A loud sounding chanter needs drone power to balance it and is possibly the reason why tenor drones were added. With softer sounding pipes, a single drone is quite adequate. Most pipers today play in bands and many have never heard the harmonics of their instruments. Indeed many seem not even aware or caring of their presence, blissfully "playing" an un tuned pipe.

Wood is a major factor in the production of tone and harmonics. Of course, every piece of wood responds differently. Density affects the resonance of the wood and is of major importance. A fine hard texture and closeness of the grain will give the best tone.

Moisture must also come into the equation because, over time, it will cause shrinkage to the bores and bore diameter affects amplitude and brightness of sound. When purchasing a previously owned set of pipes, one must be alert for warpage and elliptical bores. Otherwise, dimensional stability will be lost.

The stocks of the instrument are all important in producing steady tone. It is here that harmonics are also produced. The stock will definitely affect the behaviour of the reed as well. The volume of air in the stock and in its mouth actually controls the frequency of sound produced in the drone. This is why in the ancient world wax was used in the stock to adjust the behaviour of the drone. Antique pipes have very long stocks and it is felt that they enabled the pipes to stay in tune for longer periods, perhaps condensing water more efficiently than today's shorter stock. The stocks of these older sets of pipes also had greater internal diameter and it is felt by some that this controlled the velocity of air going up to the drones.

The bag also produces its share of harmonics and many pipers feel the Icelandic sheepskin, because of its small pores, give the most harmonics and actually add to overall amplitude. We can now see how each component of the bagpipe inter reacts with the whole and has its share in the overall production of tone and volume.

Reeds of course are a study in themselves. The constant opening and closing of the reed tongue results in both even and odd harmonics. Anyone assuming that jamming a reed, cane or synthetic, into a drone without adjusting it to its drone, is just asking for cacophony and would perhaps be better directed to the disciplines of the tin whistle, but then one would not be able to wear the kilt, which seems to be a main motivation for murdering the Bagpipe in many pipe bands.

It is obvious that the bagpipe must have a constant air supply in order to maintain tone and balance. The slightest over or under blowing will force the instrument out of tune. If one had to turn a page of music, for instance, the pressure and consequently the harmony of the instrument would be lost. This is why all of the piper's music must be memorized.

References

Observations by:

Piping Times:
Alex R Carruthers "Characteristics of the Sound Levels of the Highland Bagpipe"
John M A Lenihan and Seumas MacNeill "The Scale of the Highland Bagpipe"
Seumas MacNeill "The Pitch of the Pipe"

Proceedings of The Piobaireachd Society:
Alexander C Mackenzie
"Some Recent Measurements on the Scale of the Great Highland Bagpipe"

"Piobaireachd and its Interpretation" Dr. Frank Richardson and Seumas MacNeill
"The Highland Bagpipe and its Music" Roderick D Cannon
"The Traditional and National Music of Scotland" Francis Collinson
"Bagpipes" Anthony Baines\Oxford University