What is the reason for pitch inflation?

Question

There's this phenomenon among instrumentalists to constantly raise the pitch of the concert A. This generally occurs among string players, since the range of tunings for woodwinds, for example, is often severely limited or nonexistent. Wikipedia (or rather, one of its editors) claims the reason for this is:

This "pitch inflation" seemed largely a product of instrumentalists' competing with each other, each attempting to produce a brighter, more "brilliant", sound than that of their rivals. (In string instruments, this is not all acoustic illusion: when tuned up, they actually sound objectively brighter because the higher string tension results in larger amplitudes for the harmonics.) This tendency was also prevalent with wind instrument manufacturers, who crafted their instruments to play generally at a higher pitch than those made by the same craftsmen years earlier.

Out of curiosity, I started browsing through the edit history; the above quote has existed in (almost) its current form on another page since 2006, and the information can be dated back to September 2002. The rationale seems to make sense, but it's very tenuous to make that claim without backing it up, especially since it was made by some editor 7 years ago.

I tried to find some actual research in this field, but my searches at scholar.google.com were fruitless, as were searches of various online databases.

So, basically, is it true that pitch inflation can be attributed to the sound sounding more "brilliant" at higher frequencies? And if so, what makes it sound that way?

Answer 1

Variations in pitch and tuning systems stem all the way back to Renaissance / pre-Renaissance. Before a standard tuning system was codified, musicians in each city basically had their own tuning system, and instrument makers were limited with what they could do. The result was that if musicians from different towns / cities met, they wouldn't be able to play with one another as their instruments were not in tune.

Once technology increase, tuning systems were able to be consistent across countries - thereby improving consistency of sound and instrument creation.

To this day, pitch still continues to vary, though it is purely by choice relating to preferred aesthetics. For example, here in the US, "A" is tuned to 440hz, while in Europe, it may be 442 or higher. The reason for this is exactly the question you posed in your post - that Europeans desire a slightly more brilliant sound. Pitch inflation itself cannot be attributed to an ensemble's brilliant sound, but it can be attributed to an ensemble's desire for a more brilliant sound.

So, how does it work?

It is the same reason why audio engineers boost higher frequencies on cymbals for the extra bright, crisp sound. It works through the way sound waves resonate.

I will omit all the figures and pictures that would make this explanation easier, and unfortunately only provide a very brief overview for sake of time.

Think about the overtone series. On a string, touching the string at specific nodes will generate different divisions of the wave that still divide evenly into the original vibration of that string. Let us say that you now have a second string, tuned slightly higher, but for all intents and purposes is perfectly in tune with itself. Played by itself, it will still yield all of the same overtones from the same string divisions, however, when compared to the original string, the sound waves of each string resonating openly will not align. Since the second string is tuned slightly higher, its sound waves will be sounding ever so slightly faster than the original string. This discrepancy between strings causes the second string to stand out over the first, creating what most musicians consider to be a more "brilliant" sound.

While I have never heard of individual musicians doing it, it is certainly possible for some orchestras. In the US, in a professional orchestra, they are looking for as homogenous a sound as possible. An individual performer preferring to not tune with the group would not have a job very long. Generally, an orchestra will decide what the entire group will tune to, and in my experience it has little to do with "out doing" another musician, and more to do with achieving preferred aesthetics. After all, there are many other ways to better "out do" another group.

Lastly, I must correct the quoted paragraph in the OP and say that tuning a string higher does not objectively give more amplitude to higher overtones. Technically, since the string tuning is changed, it actually gives you a completely different overtone series. However, since that series so closely relates to the original series, it gives the impression of amplification. Again, recording engineers use this technique and others to create a more "full" sound.

Hope that helps.

Answer 2

In an amateur group the pitch rising usually starts in the woodwind and brass.

Amateur brass and woodwind players who do not do any practise between rehearsals (the vast majority of amateur players) usually go sharp due to tired embouchures during rehearsals.

I have in the past played in many amateur orchestras where this has happened and it did not start in the string section. At least one orchestra had a woodwind and brass section that at the end of a concert could finish up much sharper than the strings.

Answer 3

Besides the psychological considerations, a minor but potentially significant physical point: when one tunes "up" a string instrument, one must finish by tightening the string to avoid introducing slack. If there is a delay between the string being in tune and the perception of its being in tune, at which point the increase in tension is stopped, the error will be incremental but always positive (more tension, ever so slightly too sharp). Compound this minor error over the course of centuries of iterations, in combination with psychological considerations, and one ends up with significant pitch inflation.