35
4: GENERAL PC TOPICS
Q
What are samples, waveforms, and wavetables?
A
Simply put, a sample is basically a digital representation of an analog sound, whether it be a piano, an
animal sound, or the sound of breaking glass. Analog sound waves must be converted into binary form
(ones and zeros) before they can be stored and processed by a computer. This conversion is
accomplished by taking pictures (samples) of an analogue waveform (picture of a sound wave) at
regular intervals thousands of times each second. The end of the sample is then linked to the
beginning, forming a continuous loop. A wavetable is a collection, i.e., a library, if you will, of these
waveform samples.
Q
What does the term ‘sampling rate’ mean?
A
The sampling rate indicates the speed, measured in thousands of cycles per second, at which analog
audio is converted to digital, or digital audio is converted back to analog. The measurement is
expressed in kilohertz (kHz), so a sampling rate of 44.1kHz would equal 44,100 samples per second.
High sampling rates obviously deliver more accurate representations than low sampling rates because
they capture more information about the sound.
Q
What are DACs and ADCs?
A
A DAC is a digital-to-analog converter. An ADC is an analog-to-digital converter. A DAC is used to play
back digital audio and an ADC is used to digitally record analog audio. Most soundcards have DACs
that play back audio with 16-bit.
Q
What other Yamaha web sites provide information?
A
Try the following:
www.yamaha.co.jp/english/xg
www.yamaha-xg.com
Q
What is Acrobat Reader?
A
Acrobat Reader is a utility that gives users on both Macintosh & PC platforms the ability to read
documents stored in the PDF (Portable Document) Format.
FAQ/E 5/21/98 9:14 PM Page 35
