tions, furnished BM/E with some additional guidelines for Special Effects In Sound the use of special effects, along with valuable and fas- cinating explanations of the psychoacoustic reactions that to get one of the new special effects devices, plus an make the various sounds interesting and attractive. The equalizer that can be patched in. following is a summary of his discussion. She makes the point that the user must put the system Flanging, the original "special effect" and still the through a series of trials at some length to learn just what it most heavily used, comes in innumerable varieties today does, how all the various effects actually sound. Then the and holds its prime place in the special effects "battery" user's taste and imagination will lead to the right applica- because of this variety and because of its basic psycho - tions: the user must be familiar enough with each sound to acoustic power. Flanging can produce, among many other decide if that particular sound is really the desired one. By things, an illusion of pitch change without an actual trying the capabilities of the device in every available change of pitch: the program material retains its identity, setting of the controls, the user gets this essential familiar- but extremely interesting variations can be introduced. ity. Special effects are, in general, interesting if they give the In the most general terms, some of the main effects the brain something to do, to pay attention to. The wandering user will have with many modern delay devices include or rising or falling pitch, on top of the steady basic pitch, the following: can be extremely interesting. Many virtually indescriba- Flanging. Combining a program with delayed repeats ble effects are available in flanging, with sounds that of itself, for an enormous variety of "swimming," "vibr- "shimmer" or "shake" or vibrate, all without losing the ance," "spacy" effects (see further discussion of flang- identity of the original material. ing in Stephen St. Croix's comments, below). Another psychoacoustic virtue in delay effects is that Echo. Longer -spaced repeats become echo; double or many of the disruptions produced are quite similar to the triple echoes can provide many kinds of space effects; disruptions the external ear produces in sounds that are very long echoes suggest outer space. Echoes, too, come moving past the hearer. This gives a feeling of motion in many varieties, including "slap," "cloud," and that, again, is extremely interesting to the psychoacoustic others. system in the brain. The more complex these effects Vibrato. A single instrument or group can get more (without losing a "home base"), the more intriguing. The "life" with vibrato, just as the string player adds alive- Time Modulator supplies complexity by having two sepa- ness by using a finger on the string for vibrato. rate delay lines that can be locked together. Automatic double tracking. This adds a repeat of a The provision of a close "follower" for each sound in sound right behind it, for "fattening" (see also Stephen the original material - automatic double tracking - is St. Croix's comments on this). very widely used today for "fattening" a voice or musical Arpeggio. Anyone who reads music will know exactly passage. But an exact follower, one that simply repeats what this does - chords are spread out in time, one note the leading sound precisely a very short time later, turns after another. But new variations are available: the arpeg- out to be far less interesting, less "natural," than a fol- gio, for example, can be fed back on itself for a musical lower that has a certain amount of variation, of "error." If effect of tremendous vitality. the doubling sound goes a bit sharp and flat in a more or Doppler. The train -at -the -crossing effect, everybody's less random pattern, it sounds much more "real " than a example of a psychoacoustic phenomenon, can be straight perfect doubler, and the original sound gets the bigger, or, again, altered in many ways. "fatter" quality sought. Many pop singers today using Stephen St. Croix of Marshall Electronics, whose Time automatic double tracking have chosen the "natural" Modulator is already in use at several hundred radio sta- effect of the follower that does not follow precisely. The general verdict is that the listener can't tell it's not "real." The Time Modulator can produce metallic or otherwise Suzanne Ciani, virtuosa of electronic music, sounds, and effect strange voices and was used for the voice of Darth Vader in Star Wars and for the outer -space voices in Alien. The trick is to alter the voice quality drastically without losing intelligibility. The Time Modulator does this by removing all the vowel sounds (the "voiced" sounds) but keeping the fricatives (the consonant sounds) in the original. The spaces in time occupied by the vowels are preserved and can be filled with the voice sounds after they have been radically processed in the delay line. For example, all ups and downs in pitch of the vowel sounds can be removed for a "dead tone" effect; in addition, the frequency re- sponse can be drastically skewed for a thin or hard or squeaky sound, or whatever else is wanted. One of St. Croix's important general comments was that a special effects device must have extremely low noise and distortion of its own and cover the total audio range to preserve the full character of the various sounds. Many of the flanging sounds, for example, have ex- tremely complex harmonic structure, including compo- nents at the limit of the range. Any failure to reproduce this harmonic structure with total fidelity will dilute the effect, reducing its power and interest. BM/E

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