Файл: Sound Tech Terms Dictionary.pdf

Appendix C

Each waveform contains a unique profile of har-
monics which determines its characteristic timbre.

The sine wave is a “pure” tone, i.e., one which
contains no harmonics.  It is used in additive
synthesis to build up more complex sounds, in
analog synthesis for LFO modulation (such as
vibrato and tremolo), and also as an audio test
signal.

The sawtooth waveform, in contrast, contains all
the harmonics in the audio range, although not in
the same quantities.  The loudness of each har-
monic is inversely proportional to its frequency,
so the harmonic with double the frequency of the
fundamental is at half the volume, three times
the frequency is at a third the volume, etc.  This
makes an ideal waveform for producing fuller
sounds as it contains all of the frequencies re-
lated to the fundamental.  The sawtooth may be
either rising or falling.

The square wave contains only odd-numbered
harmonics, again in inverse proportion to their
frequency.  The hollow sound produced by the
square wave sounds much like the clarinet.

The square wave is actually a special case of the
pulse wave, where the negative and positive sec-
tions of the cycle are of equal duration.  It is the
variable nature of the pulse wave which makes it
interesting in sound synthesis.  Not only are
there infinite variations on the harmonic spectra
available, but the pulse width may be swept.
This is known as pulse width modulation.  See
PWM.  The width parameter refers to the dura-
tion of the positive component in proportion to
that of the complete cycle.

The square, sawtooth, and pulse waves contain
whole families of frequencies in harmonic series.
This means that the human ear perceives these
sounds as a single pitch whose tonal quality is
determined by the exact mix of harmonics pre-
sent.

The triangle wave contains the fundamental and
a few high harmonics.  Normally found only in
analog synthesis as a variant on sine wave
modulation, but can be used as an alternative to
the sine wave for LFO modulation, producing
exponential, rather than linear variations.

 F   2  3   4   5   6   7   8   9   etc.

Harmonic Content

 F   2  3   4   5   6   7   8   9   etc.

Harmonic Content

 F   2  3   4   5   6   7   8   9   etc.

Harmonic Content

 F   2  3   4   5   6   7   8   9   etc.

Harmonic Content

 F   2  3   4   5   6   7   8   9   etc.

Harmonic Content

 F   2  3   4   5   6   7   8   9   etc.

Harmonic Content

Varies with width

Varies with time

Sine Wave

Triangle Wave

Square Wave

Pulse Wave

Pulse Width Modulation

Sawtooth Wave

Rising
Falling

Appendix D

20

30

40

65

80

150

200

400 500

1K

2K

4K

8K

16K

CDEFGAB

CDEFGAB

CDEFGAB

CDEFGAB

CDEFGAB

CDEFGAB

CDEFGAB

CDEFGAB

CDEFGAB

CDEFGAB

C

20

30

40

65

80

150

200

400 500

1K

2K

4K

8K

16K

Soprano

Contralto

Tenor

Baritone

Bass

Small

Medium

Large

Tuba

Bass Trombone

Tenor Trombone

French Horm

B-Trumpet

Contrabassoon

Alto Saxophone

Bass Clarinet

English Horn

Bassoon

B-Clarinet

Oboe

Flute

Piccolo

Harp

Viola

Guitar

Bass

Cello

Piano

Pipe Organ

Violin

Frequency (Hz)

Singing Voice

Kettle Drums

Brass

Woodwinds

Strings

Bibliography

0.

Buick, Peter and Vic Lennard, Music Technology Reference Book. PC Publishing, Tonbridge, Kent, UK, 1995.

If you have any use at all for this dictionary, you need one of these. Several, in fact

. 

1.

Evans, Alvis J., Making Sense of Sound: The Basics of Audio Theory and Technology. Prompt Publications, Indianapolis, IN, 1992 (2nd Ed.)

2.

Petersen, George and Steve Oppenheimer, Tech Terms: A Practical Dictionary for Audio and Music Production. EMBooks, Emeryville, CA,

1993. 

3.

White, Glenn D, The Audio Dictionary. University of Washington Press, Seattle, 1991 (2nd ed.) Very technical and very good. Excellent

graphics, excellent sense of humor, excellent appendices. Only criticism: needs to be updated to include digital music, including MIDI. 

4.

Wilkie, Godric. The Studio Musicians Jargonbuster. Musonix Publishing, London, 1993. A good, entertaining, introductory dictionary. 

5.

Cummings, David, Ed., The Hutchinson Encyclopedia of Music. Helicon Publishing, Ltd., Oxford, England, 1995. 

6.

Sinclair, Ian R. Introducing Digital Audio: CD, DAT and Sampling. PC Publishing, Tonbridge, Kent, UK, 1988 and 1992. Extremely

technical, extremely detailed explication of CD and DAT formats, standards, and production. 

7.

Wadhams, Wayne. Dictionary of Music Production and Engineering Terminology. Schirmer Books, New York, 1988. Basically a good

book, especially for anyone contemplating doing sound-for-film. Unfortunately, there are lots of errors, the book is poorly cross-referenced, and

in parts, just inscrutable. 

8.

"Music & Computers" Magazine. Miller Freeman, Inc., San Francisco, CA. 94107. 

9.

"Keyboard" Magazine. Keyboard, San Mateo, CA. 94402. 

10. "Mix" Magazine. 6400 Hollis St., #12, Emeryville, CA 94608, especially "Whats a Binky?" March, April, and June 1999, by Larry Blake. 

11. "Recording" Magazine. Music Maker Publications, Inc., 7318 Topanga Canyon Blvd., Suite 200, Canoga Park, CA 91303. 

12. "Sound on Sound" Magazine. Media House, Burrel Road, St. Ives, Cambs. UK, PE17 4LE. 

13. "Sound on Stage" Magazine. Media House, Trafalgar Way, Bar Hill, Cambs. UK, CB3 8SQ. 

14. Timeline. SMPTE Made Simple. Timeline Vista, USA. 1996. Such that SMPTE timecode can ever be simple, I guess this is it. 

15. White, Paul. The Sound on Sound Book of Music Technology: A Survivors Guide. Sanctuary Publishing Ltd., London, 1997.

Feedback

Any comments, questions, additions, or critiques on any aspect of this dictionary, please feel free to contact the following people: 

Sandy Lerner

author

Sandy@xkl.com

Len Bosak

engineer, cisco co-founder

Bosak@xkl.com

Dan Shores

engineer, musician

SonoLuminus@xkl.com

Allan Kent

editor

allank@quixnet.net