User Manual

Scorpio Preliminary User Guide
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phantom power
Condenser (capacitor) microphones require power for operation. They
use power to charge the diaphragm backplate (for true condensers)
and power the impedance convert located adjacent to the micro-
phone capsule. Phantom power is the method for microphone inputs
to supply DC power to the microphone through the same connection
used for the audio signals from the microphone.
Phantom power provides a positive voltage, typically between 11-52
VDC, with 48 V being the most common, on both pin-2 and pin-3 with
pin-1 used as ground. The DC voltage appears as a common-mode
signal on the balanced connection and is rejected by the connec-
tion’s differential amplier. Phantom power has no effect on dynamic
microphones.
Digital
AES3
a standard for the exchange of digital audio signals between pro-
fessional audio devices. An AES3 signal can carry two channels of
PCM audio over balanced, 110 ohm interconnections. AES3 is most
commonly interconnected with XLR-3 cables.
AES42
a digital interface protocol for microphones and microphone inputs.
Microphones conforming to this standard directly output digital audio
through an XLR or XLD male connector, rather than producing an
analog output. AES42 microphones require powering.
sampling rate
When converting between analog and PCM digital audio, the analog
signal is measured (sampled) in unique steps at a data rate specied
in kHz. Higher sampling rates allow for representing higher frequency
analog audio. 48 kHz is the standard sampling rate for production
worldwide. Higher sampling rates including 96 kHz and 192 kHz
are used for high-precision applications where the representation of
audio above 20 kHz is required. A general rule is that the maximum
analog audio frequency is ½ the sampling rate.
bit depth
When converting between analog and PCM digital audio, the ampli-
tude of an analog signal is measured in nite steps, measured in bits.
Higher bit rates result in greater resolution of amplitudes, resulting
in higher dynamic range. 24-bit audio, with a theoretical maximum
dynamic range of 144 dB, is the standard bit depth used throughout
the audio chain for production.
word clock
A reference signal used to synchronize the sampling rate of multiple
digital devices.
Dante
a combination of software, hardware, and network protocols that
deliver uncompressed, multi-channel, low-latency digital audio over a
standard Ethernet network using Layer 3 IP packets.
Input Settings
stereo linking (inputs)
When active for stereo sources such as stereo microphones, linked
inputs are hard panned to the left and right bus. Controls including
gain (trim), fader, high pass lter, delay, limiter, mute, and routing are
controlled together.
mid-side linking (inputs)
When mid-side (MS) stereo inputs are used and the inputs are set to
MS linking and MS decoder is activated for those inputs. This yields a
stereo signal with one fader controlling overall input level and the oth-
er fader controlling the “width”, or amount of the side signal added.
With an MS matrix at the input, the signal is sent to an output bus as
left/right stereo. Mixers with MS matrices often allow for discrete mid
and side signal recording. In that case the MS decoder can be activat-
ed at the headphone selection to monitor left/right stereo.
channel grouping
With Scorpio any of the rst 16 channels can be grouped together
so that their faders, record arming states and mute states can be
controlled together. Channel grouping can be used as an alternative
to sending channels to a bus.
delay (channel)
Time delay that can be applied to an individual channel. Channel
delay, typically set in milliseconds, is often used to compensate for
different acoustical or electrical arrival times of signals between
channels.
pre-fader routing
The signal from a channel is routed to a bus before the fader in the
signal path. The input trim, if available, controls the channel level sent
to the bus. Isolated tracks are typically recorded pre-fader so that any
level changes made to the faders don’t affect the recorded signal.
post-fader routing
The signal from a channel is routed to a bus after the fader in the
signal path. The fader controls the level of the channel at the bus.
Channels sent to a master bus, such as the left/right bus, are typical-
ly sent post-fader.