Crane Song Avocet IIA Quantum DAC User manual

Avocet IIA
Quantum DAC
VER 2 20151022
New DAC
The Quantum DAC is the 5th generation design from Crane Song with ultra low jitter.
The Quantum DAC uses 32 bit a converter and ASRC for jitter reduction up sampling to
211KHz. Avocet has always upsampled to 211KHz. The reference clock has less then
1pS, 0.5pS typical 1Hz to 100KHz and a proprietary reconstruction filter for accurate
time domain response.
New
Direct sub woofer outputs for each of the three output have been added.
The output levels are now programmable in 0.25 db steps for speaker level matching

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NOTE:
There is information in the Avocet II manual that applies to the Avocet IIA
This information will be added to this doc at some point in time

Input selection
The DAW input will be S/PDIF,
AES or Optical selected in
Shift mode.Digi- 1, 2 are AES,
the analog inputs are Bal-
anced
Talk back button sends the
talk mic into the head-
phone output. It is push-on
push-off, however holding
it for 2 seconds allows
quick release - non latching
Truncates the digital input to 16 bits. For
checking what 16 bits sounds like
Input level when
Phones or Dim modes are
not selected
1 DB steps through most of
the range
Mute kills the main output.
On power up Avocet is
muted
Monos the
stereo source
Dims the main audio path. The dim level
is set by turning the level while dim mode
is active.
Selection of phones is over ridden by
selecting dim.
Changes the
phase of one
channel, disabled
in surround mode
SHIFT MODE
to reach the setup
functions (they have the
smaller text on the panel)
Selects which
speaker output
1 of 3
Channel Selection
to 7.1 surround
3
MAIN FUNCTIONS

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By pressing all three output selection buttons
at the same time Avocet will reset all of it’s
internal settings. This is the same as rebooting
the remote.
All gains, main and phones are set to zero
Output 1 is the selected output
DAW is the input selected
Phones are set to the Aux input
Stereo speaker selection is selected
All offsets are cleared
CLEARING THE INTERNAL SETTINGS
System Reset

TALKBACK OPERATION
Talk mic is on when
the LED is on. It has
push-on, push-off operation or
latching. However if the talk button
is held for one half second or
more, the talk back releases when
the button is released,
non latching
The dim monitor level can be set when the
talkback button is pushed. The monitors can
be dimmed to off or a level that is below
feedback. This will allow comminution in
both directions while in talk mode.
When in talkback all other buttons are
locked out until talkback is released
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Gain Trims are adjustable
by plus or minus 10db
on all INPUTS and the
MONO function in surround
GAIN TRIMS
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If one presses and holds the input select button a second time it will enable the input
gain trim mode. It requires about one half second of hold time to enter the trim mode.
Trim mode allows changing the input level on the selected input relative to all other
inputs. Gain trim has an offset range of plus or minus 10 db in 1 db steps. It is adjusted
by turning the GAIN knob. By pressing the input button a third time, the input will return
to normal operation while remembering the gain trim. Selecting any other input will also
exit the trim adjust mode.
Gain trim can be cleared, locked or enabled by using the Shift key to reach the desired
selection. See shift mode setup functions
The mono function also has a gain trim for level matching in surround. After selecting
mono a second time, if one presses and holds the mono select button for one half
second or more Avocet will enter the mono gain trim mode. To leave the gain trim mode
press the button again. This will cause the gain trim to be remembered and the mono
mode to be exit.
In normal operation all input gains will track. At the end of the stepped attenuator range
the offset gains could reach a limit where they will not change. As an example if you
trim an input up by 10 db and then move the main gain to max that input will be max
+10 which is not possible. Bringing the main gain back down, the 10db offset will still
exist. The same thing will happen on the bottom end of the control range.

SHIFT MODE SETUP FUNCTIONS
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Gain trim can be cleared, locked or enabled by using the Shift key to reach the desired
selection.
Clearing the offsets set all input trims and the mono trim to 0 so all inputs are at the
default setting. The mono trim works in surround mode only.
Locking and unlocking the trims prevent unintended changing of the trims or allow
access to the trims. The hold down timer and the led flash will not happen
when offsets are locked.
This is for input level matching.
SHIFT MODE GAIN TRIM FUNCTIONS
Gain trim offset clear
Gain trim offset lock
Gain trim unoffset lock
must be in shift mode
to enable these functions
SHIFT KEY TO ENABLE SHIFT MODE
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SHIFT MODE SETUP FUNCTIONS
Changes DIM
from relative LEVEL
to absoulte LEVEL
In the Shift Mode Select the
source for the DAW input between
AES, SPDIF, OPTICAL
.
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Changes output 3
to work in parallel
with outputs 1 and 2
for use as a sub woofer
output
Functions F1, F2
for future features
F3 allows turning both
ANALOG 1 & ANALOG 2
at the same time
it mixes the 2 inputs

TALK BACK MIC GAIN is changed by
selecting the TALK button
when in the SHIFT MODE.
Turning the gain knob
changes the mic gain. The gain steps
are 3 db steps to 72 db of gain
GAIN
SHIFT MODE TALK BACK GAIN FUNCTIONS
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