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
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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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SHIFT MODE GROUP FUNCTIONS
The group function is reached by the shift button and
then selecting the group button. What it does, is in
surround mode, it groups together Left, Right, Cen-
ter to function as one button, Surround Left and
Surround Right as one button, and Extra Left and
Extra Right as one button
This showes the key grouping
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SHIFT MODE HEADPHONE SETUP
Headphones / shift to select phones control
Dim Button over rides
Headphone mode
Headphone Level
Selects direct AUX analog
input for the Headphone
output
The headphone source is
selected by the main input
buttons. It’s level does not
change with the main
system level
The headphone source
is selected by the main
input buttons. It’s level
changes with the main
system level
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By pressing any one of the speaker select buttons a second time
and holding it for about 0.5 seconds will put Avocet into the speaker
set up mode.
If SHIFT is selected the speaker setup is disallowed.
Selecting the center channel button will cause the center channel
be the mono speaker when selecting mono. This is the surround
mode of operation
Selecting the left, right, or both, (left and right) will disable the sur-
round channels. This selects which speaker is the mono speaker,
when the mono function is selected. This is the stereo mode of
operation
To exit the setup mode touch the output select button a second time
During Speaker setup the Sub Woofer mode is disabled.
Once set up, switching between the speaker systems is user trans-
parent.
SPEAKER / OUTPUT SETUP
Stereo to Surround
Direct Sub mode and Speaker Gain Trim
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SPEAKER MODE SETUP
In the speaker mode setupthe following thing are controled for each speaker or output
Mono Speaker, L, R, or center for surround
In OUT1 setup there is a transparent mode for surround on all outputs
The transparent mode removes some of the lock outs that exist when in stereo
the center speaker will be used for the mono speaker
New to Avocet IIA
Direct Sub Out can be turned on or off for each of the outputs
Level matching of the 3 speaker outputs is set by turning the knob, external pads are no longer
required
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SPEAKER SETUP OUT 1
Transparent Surround Mode
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TRANSPARENT SURROUND SETUP
turning this button on
will cause the unit to be in surround
mode at all times
(Transparent Surround `Mode)
the mono speaker select
function determines the
active speakers when mono is selected
MONO SPEAKER
SELECT
Selects which speaker
is the mono output
when mono is selected
Selecting the CENTER
will put Avocet into
Surround mode for the
selected output
DIRECT SUB MODE
By selecting this function
which must be set in each
output the Direct Sub
output is turned on when
the OUT1 is selected
The OUTPUT LEVEL of each speaker may be trimmed down for speaker level matching.
When setting up the system so that the normal listening level is around 0 on the dial.
When entering the speaker / output setup. No reduction in level is indicated with the level leds
showing 0. The speaker trims are in 0.25 db for a max trim of -15.75db. There are 4 steps per db or
8 steps to get to the -2 setting on the dial.

SPEAKER SETUP OUT 2
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MONO SPEAKER
SELECT
Selects which speaker
is the mono output
when mono is selected
Selecting the CENTER
will put Avocet into
Surround mode for the
selected output
DIRECT SUB MODE
By selecting this function
which must be set in each output
the Direct Sub output is turned
on when the OUT2 is selected
The OUTPUT LEVEL of each speaker may be trimmed down for speaker level matching
And setting up the system so that the normal listening level is around 0 on the dial.
When entering the speaker / output setup. No reduction in level is indicated with the level leds
showing 0. The speaker trims are in 0.25 db for a max trim of -15.75db. There are 4 steps per db or
8 steps to get to the -2 setting on the dial.

SPEAKER SETUP OUT 3
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MONO SPEAKER
SELECT
Selects which speaker
is the mono output
when mono is selected
Selecting the MONO SPK
will put Avocet into
Surround mode for the
selected output
DIRECT SUB MODE
By selecting this function
which must be set in each output
the Direct Sub output is turned
on when the OUT3 is selected
The OUTPUT LEVEL of each speaker may be trimmed down for speaker level matching
And setting up the system so that the normal listening level is around 0 on the dial.
When entering the speaker / output setup. No reduction in level is indicated with the level leds
showing 0. The speaker trims are in 0.25 db for a max trim of -15.75db. There are 4 steps per db or
8 steps to get to the -2 setting on the dial.

DUAL FUNCTION ON THE ACCESSORY CONNECTOR
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Original Accessory pin out
Stereo Accessory pin out
Avocet IIA shipped configured for stereo will have the Accessory connector configured in the stereo
mode. This uses the Tascam style of signal assignment. Any one who upgrades from and earlier
version and uses the Accessory connector may need to move the internal ribbon cable

The accessory connector can have 2 different functions
In the Avocet IIA stereo mode the accessory connector has the following signals avaliable
using the Tascam pinout. All outputs are line level
In Surround configurations the pin out has not changed. The Accessory connector pinout can be
changed by moving an internal ribbon cable between 2 different ports
CH1= Direct Sub Right
CH2 = Direct Sub Left
CH3 = Phones Left
CH4 = Phones Right
CH5 = Talk Output
CH6 = talk back switch input
CH7 = Meter Left analog
CH8 = Meter Right analog
PINOUT DETAILS STEREO
SIGNAL
CH1_HOT 24 SUB RIGHT Symmetrical TO UNBALANCE DO NOT CONNECT XLR PIN 3
CH1_COLD 12
CH1_GND 25
CH2_HOT 10 SUB LEFT Symmetrical TO UNBALANCE DO NOT CONNECT XLR PIN 3
CH2_COLD 23
CH2_GND 11
CH3_HOT 21 PHONES LEFT PIN2 SIG-
CH3_COLD 9
CH3_GND 22
CH4_HOT 7 PHONES RIGHT PIN2 SIG-
CH4_COLD 20
CH4_GND 8
CH5_HOT 18 TALK OUT PIN2 SIG-
CH5_COLD 6
CH5_GND 19
CH6_HOT 4 ext talk cmd in
CH6_COLD 17 hot to gnd for talk on
CH6_GND 5
CH7_HOT 15 METER LEFT PIN 2 SIG +
CH7_COLD 3
CH7_GND 16
CH8_HOT 1 METER RIGHT PIN 2 SIG +
CH8_COLD 14
CH8_GND 2
DUAL FUNCTION ON THE ACCESSORY CONNECTOR
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ACCESSORY CONNECTOR PINOUT DETAILS SURROUND MODE
1 Right Channel Source Output
2 gnd
3 gnd
4 talk mic output - When talk button is pushed (Mic Output)
5 Right phones out (Line level phone bus)
6 Left phones out (Line level phone bus)
7 gnd / ground
8 data I/O do not connect
9 gnd
10 gnd
11 gnd
12 Surround mono input 6
13 Surround mono input 5
14 Left Channel Source Output
15 mono out
16 talk command in - enable by tying to gnd
17 mute+
18 mute-, solo-
19 solo+
20 used in surround wiring from left-right to center channel
21 gnd
22 Surround mono input 1
23 Surround mono input 2
24 Surround mono input 3
25 Surround mono input 4
To use the external mute or solo inputs 5 to 15 volts needs to be applied to the control input lines.
Polarity must be followed. These inputs are optical isolated.
The mute control is push on - push off, the talk input is also push on - push off
or latching. The solo switching remains in the soloed state as long as the control voltage is applied.
A jumper is provided on the main pcb that selects either the solo is the DAW or ANA1 input as the
solo input.
All audio signals are unbalanced
Starting with the rev5 pcb the low connection for mute and solo has changed
See the section on headphone setup and the external wiring connections.
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