Yamaha Programmable Mixer 01 User Manual page 119

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Glossary
Peaking — A type of EQ circuit used to cut and boost a band of fre-
quencies. It produces a mountain-peak type response curve. The
width of the frequency band is controlled by the Q parameter. Mid-
band EQ is usually of the peaking type. Compare with Shelving.
PCM — An abbreviation for Pulse Code Modulation. In the second
part of the A/D conversion, the pulses derived using PAM are con-
verted into binary data words using PCM. See also PAM.
Q — The unit used to measure an EQ circuit's selectivity. For high
values the frequency band is narrow. For low values, it is wide.
ProMix 01 Q is stated in musically intuitive octaves.
Quantization — The PCM process where PAM pulses are approx-
imated to the nearest binary value available. In the ProMix 01 20-bit
system, pulses can be approximated to any one of 1,048,576 binary
values. That's four times more than a 16-bit CD system. These
approximations can result in quantization errors (i.e. noise). How-
ever, this is reduced by oversampling, as featured on ProMix 01.
Pink noise — A type of random noise that contains an equal amount
of energy per octave. The bands 100–200, 800–1600, and 3000–6000
all contain the same amount of energy. White noise, on the other
hand, has an equal amount of energy per frequency band. That is,
100–200, 800–900, and 3000–3100.
Program Change — A type of MIDI message that is used to recall
programs and patches. On the ProMix 01 they recall mix scenes.
RAM (Random Access Read & Write Memory) — A type of
memory chip that stores data that can be edited, but requires a con-
tinuous electrical charge. ProMix 01 mix settings and mix scenes are
stored in RAM. An internal backup battery provides the continuous
charge. Contrast with ROM.
Register mode — The mode in which all MIDI Control Change
messages used to control ProMix 01 parameters are transmitted on
the same MIDI channel and MIDI Control Change 98 (Non Regis-
tered Parameter LSB) is used to identify banks.
ROM (Read Only Memory) — A type of memory chip that stores
data that cannot be edited, but does not require a continuous electri-
cal charge. The ProMix 01 operating system is stored in ROM. Con-
trast with RAM.
Sampling frequency — The number of times per second that an
analog audio signal is sampled (measured) during A/D conversion.
The value of each sample is stored as a data word. Once in the digital
domain, the data usually remains at the same sampling frequency
until final D/A conversion.
Scene memory — A ProMix 01 memory location used to store a
mix scene. See also Mix scene.
ProMix 01 User's Guide