MOTU 828x 28x30 Audio Interface with ThunderTechnology - Manual (Page 15)

A B O U T T H E 8 2 8 X
15
Metering section
The front panel of the 828x displays several banks
of input and output metering. The threshold for
these lights is approximately -42 dB. The four- and
five-segment input meters provide dedicated
multi-segment metering for their respective inputs,
as do the five-segment main out meters.
Two ten-segment meters for the two front-panel
mic/guitar inputs show input levels from -42 to -1
in the first column of LEDs, plus an additional
range in a second column from zero to +12 dB
(including clip). Both inputs are equipped with V-
Limit™, a hardware limiter. With the limiter turned
off, signals that hit zero or above will clip (a hard
digital clip). However, with V-Limit turned on,
signals can go as high as +12 dB above zero with no
digital clipping. If the signal then goes above +12
dB, it will clip, even with V-Limit engaged.
The Clock lights indicate the global sample rate (as
chosen in the MOTU Audio Setup software). The
LOCK and TACH LEDs provide feedback for the
828x’s on-board SMPTE synchronization features.
The ADAT and MIDI LEDs indicate audio and
MIDI activity, respectively.
16-BIT AND 24-BIT RECORDING
The 828x system handles all data with a 24-bit
signal path, regardless of the I/O format. You can
record and play back 16-bit or 24-bit audio files at
any supported sample rate via any of the 828x’s
analog or digital inputs and outputs. 24-bit audio
files can be recorded with any compatible host
application that supports 24-bit recording.
CUEMIX FX 32-BIT FLOATING POINT
MIXING AND EFFECTS
All 828x inputs and outputs can be routed to the
on-board CueMix FX 16-bus (8 stereo) digital
mixer driven by hardware-based DSP with 32-bit
floating point precision. The mixer allows you to
apply no-latency effects processing to inputs,
outputs or busses directly in the 828x hardware,
independent of the computer. Effects can even be
applied when the 828x is operating stand-alone
(without a computer) as a complete rack-mounted
mixer. Input signals to the computer can be
recorded wet, dry, or dry with a wet monitor mix
(for musicians during recording, for example).
Effects include reverb, parametric EQ and
compression/limiting. The 828x’s Classic Reverb™
provides five different room types, three frequency
bands with adjustable crossover points, shelf
filtering and reverb lengths up to 60-seconds.
Two forms of compression are supplied: a standard
compressor with conventional threshold/ratio/
attack/release/gain controls and the Leveler™, an
accurate model of the legendary LA-2A optical
compressor, which provides vintage, musical
automatic gain control.
CueMix FX also provides 7-band parametric EQ
modeled after British analog console EQs,
featuring 4 filter styles (gain/Q profiles) to
effectively cover a wide range of audio material.
Low-pass and high-pass filters are also supplied
with slopes that range from 6 to 36 dB. The EQ
employs extremely high precision 64-bit floating
point processing.
The 828x’s flexible effects architecture allows you to
apply EQ and compression on every input and
output (a total of 58 channels), with enough DSP
resources for at least one band of parametric EQ
and compression on every channel at 48 kHz.
However, DSP resources are allocated dynamically
and a DSP meter in the CueMix FX software
(included) allows you to keep tabs on the 828x’s
processing resources. Each input, output and mix
bus provides a send to the Classic Reverb
processor, which then feeds reverb returns to mix
busses and outputs, with a selectable split point
between them to prevent send/return feedback
loops.