VIEWPOINT: 2 ESSAYS ON XENHARMONICS

(first published in Polyphony magazine, 1977)

by

Ivor Darreg

Xenharmonics (i.e., pitches, intervals, and chords which do not sound like the 12-tone equal temperament generally in use on standard keyboard and fretted instruments) has "snuck" in through the back and side doors to reach the public ear. It's not a question of whether we shall or shall not tolerate new pitches and scales; rather, it is a matter of being intellectually honest and acknowledging the existence of that which some have carefully ignored for so long.

Case in point: the familiar rotary dial on telephones is being gradually and relentlessly replaced by a pushbutton keyboard with 12 keys instead of ten dial holes. Depressing any of these buttons sounds two tones which are not related in terms of the 12-tone equal temperament. Thus, more and more people hear these sounds every day, and this will cause a subconscious change in attitude--all the more powerful in the long run because it is subliminal.

Case in point for a much longer period of time: in this part of North America, the hum of alternating-current power lines and electrical equipment such as motors, transformers, and radio sets is 60 Hz (or a multiple such as the octave above, 120 Hz). These pitches fall almost exactly on the quartertone between B-flat and B-natural -- the discrepancy is far smaller than the usual errors in tuning which we will find on most instruments. It is virtually impossible for any normal-hearing person to escape this pitch. In other parts of the world the powerline frequency is 50 Hz, a just (i.e., exact and untempered) minor third below our AMerican standard. This falls close enough to the quartertone between G and G-sharp.

An unavoidable result of all this is that when ordinary music is heard against those hums, and this occurs much of the time whether we are aware of it or not, all the intervals of the quartertone scale will be heard, albeit subconsciously. This endures throughout our lives. Under many common conditions, the odd-numbered harmonics, 1:3:5:7:9:11:13 etc. of this power-line/machinery hum will be heard also, thus creating many notes and intervals which do not occur in the "standard" scale.

Such affairs as fear ratios that must be used in machines produce musical intervals not in the 12-tone scale, and thus these sounds are impressed upon the public--often loudly. Train-whistles and auto horns of more than one tone at a time may also have accidental tunings not in the 12-tone scale.

This takes us back to another important subject: early in this century, Russolo and Marinetti, the Italian Futurists, proposed the "intoning of noises," creating a new Art of Noise based on the element of pitch in many of the mechanical noises which had recently come into their environment. They invented instruments called Intonarumori for consciously controlling and manipulating these ideas. By now, some 70 years later, all their dreams have come true with a vengeance. The problem is not how to hear these effects; it is how to escape them so that you can have some sleep.

I feel that musical-instrument manufacturers and music-teachers spend a lot of time inducing their customers and students respectively to spend much needless and futile effort ignoring the facts just presented above.

* * * *

In late August I attended an all-percussion concert at Exposition Park in Los Angeles. The only unorthodox item was an electric bass -- all the rest of the ensemble was acoustic, with more drums than I could count, vibes and marimbas galore, one grand piano, tubular bells, and the usual traps. The youngish conductor did only his own compositions and obviously had rehearsed a very tight ship with all the absolutely simultaneous attacks.

One sure missed the strings and the horns...two hours without stopping once for breath, since there were no wind instruments to compel phrasing. No singing either. But this was a most important acoustics lesson: the inharmonic partials of piano bass strings and the noise of hammering on the top notes of the piano blended perfectly with chimes, glockenspiel, xylophone, marimbas, and vibes, since these too have inharmonic components, and some of them are as loud as the nominal pitches of the tones in question. At the top end of the piano keyboard, the hammer noise is lower-pitched than are the strings and is actually louder--it is the piano-tuner's nightmare to hear the evanescent high-pitched tones through all that distracting noise. The longitudinal and possibly torsional vibrations of wound bass strings, especially in a new piano, are loud and clear this is incidentally why all the electronic imitation pianos can't quite make it. You can put in the right amount of noise and have the right envelope, but still not have these inharmonic longitudinal vibrations which are NOT in the 12-tone scale. Of course, the different kinds of tubular chimes and metal and wooden bars in the other percussive instruments have assorted inharmonic pitches that are not in the 12-tone scale either. This causes an unexpected surprising blend with the piano, which is shown to be primarily a percussion instrument, not the singing stringed instrument that the music critics of piano recitals and the teachers of Romantic period pieces keep arguing that it is.