Sample Rate Conversion - Alesis ADAT-LX20 Reference Manual

Glossary
Q
R
Record-Ready
A track mode, often called "armed." When you want to record on a track, you
"ready" or "arm" the track. When you push the record button, all tracks that are
ready or armed will go into record mode.
Rotary Head
A type of tape head, as used in the XT20, that spins at a high rate of speed in order
to create the same effect as having the tape moving by at rates not physically
possible with today's tapes and transports.
S
Safe
A track mode. When a track is safe, it is not ready for recording.
Sample Accurate Synchronization
This means synchronization is accurate not just to individual frames or milliseconds,
but to 1/48,000th of a second (with 48 kHz sampling rate). This means two
synchronized ADATs will never be more than 20 millionths of a second apart.
Sample Rate
A digital representation of an analog signal created by checking, or sampling, the
analog voltage a fixed number of times per second. The greater the number of
samples, the more accurate the representation of the analog signal. The CD uses a
sampling rate of 44.1 kHz; it checks the analog signal 44,100 times per second.

Sample Rate Conversion

Sample rate conversion is the process by which audio originally recorded at one
sample rate is converted to another sample rate. The audio is converted by shifting
its pitch up or down, and then played back at the new sample rate.
SMPTE/LTC
Society of Motion Picture and Television Engineers (SMPTE and Longitudinal Time
Code (LTC). A standard for LTC was specified by the SMPTE, and has been adopted
by the motion picture and television industries. A complete description of LTC can
be found in The Time Code Handbook, by Walter Hickman. SMPTE timecode is the
standard sync reference for professional audio and video post-production.
S/PDIF Interface
96 ADAT LX20 Reference Manual