Specifications

Control Function Table
Installation and Setup
Many AT-MX381 functions can be configured and accessed over the RS232
data port by a PC running the SmartMixer Software (included) or by an exter-
nal control system (Crestron® or AMX®) using “Open Disclosure Protocol.”
This capability along with the contact closure inputs and control voltage out-
puts accessed through the External Control Connector provides for maximum
flexibility when interfacing the AT-MX381 to other equipment.
The table below lists the AT-MX381’s controllable functions and their factory
default settings.
* Can only be accessed via 25-Pin D-sub
External Control Connector on unit.
** Note: Force-ON/OFF contact closures
override PC control fuctions. Channels
forced ON or OFF using these control
points will NOT be reflected in the PC
control system.
Function Default setting From Unit
Function accessibility
From RS232
Data (PC)
Channel Trim Minimum NoYes
Channel Level Minimum NoYes
Input Attenuation
(No attenuation; no attenuation P48; attenuation)
0 dB YesYes
Phantom Power (Per Input) Off YesYe s
Channel Priority Select (Per Input) Off YesYe s
Threshold Level Minimum YesYes
Mode (Manual/Auto Mixer) Auto Mixer YesYes
Output Attenuation 0 dB (no attenuation) YesYes
PC Control Force – ON** Off YesNo
PC Control Force – OFF** Off YesNo
Force – ON Override (Per Input) Off NoYes*
Force – OFF Override (Per Input) Off NoYes*
Direct Output Select (Pre/Post Gate) Post Gate YesNo
NOMA Off YesNo
Gate Hold Time (Per Input) 1.0 Second YesNo
Gate Attenuation (Per Input) 36 dB YesNo
Low Cut Filter (Per Input) Off YesNo
“Last Mic On” On YesNo
Output Limiter (Overall) Off YesNo
Output Level Indicator (Pre/Post Master) Pre Master YesNo
Lock Mode (Control Lockout) Disabled YesYes
Refer to the section on Computer
Control for information on connecting a
PC computer, installing the SmartMixer
Software control software and using the
software.
Out of the box, the AT-MX381 comes configured for most common applica-
tions. Here are some basic SmartMixer setup tips to help quickly get up and
running: (Items in brackets [ ] refer to control locations on the diagram.) Note
an audio line level source may be substituted for any “microphone”.
AT-MX381 SmartMixer quick setup tips:
Figure 1 - AT-MX381 Front Panel - Control Layout (Page 9)
1. Turn the Master Volume control (inner knob) to the minimum position
(counterclockwise). [5]
2. Turn the Threshold control (outer knob) to the minimum position (counter-
clockwise). [6]
3. Turn all eight Input Trim and Input Level controls to their minimum position
(fully counterclockwise). [1,2]
4. Connect the power cord to the mixer and plug into an AC outlet. (The AT-
MX381 will automatically detect and select the proper AC voltage setting
based on line voltage connected.)
5. Turn Power switch “on.” The mixer will perform a self-test and flash each
input’s Gate LED. (Power switch is on rear of SmartMixer.)
Adjusts the mixer’s overall output. Turn clockwise to increase output.
Push to select Manual or Auto Mixer mode.
6. Connect a microphone to Input 1. Select the proper input attenuation and
phantom power with the P48/ATT button. (Use a small-tipped tool to push
the recessed button.) [4]
7. Turn the Input 1 Trim control to the “twelve o’clock” position. The channel
1 LED will light green if the microphone is operational and red if the trim
control is set too high.
8. Adjust the Input 1 Level control and observe the Output Status Level
Display for proper meter indication when speaking into microphone
(peaks at 0). [9]
9. Plug in up to seven other microphones and adjust the Attenuation, Trim
and Level controls for each microphone until proper meter indication is
obtained. Select NOMA, if desired.
10. Priority can be assigned to one or more microphones by pressing its Level
control; observe the priority indicators on the Channel Status Indicator
Display.[10] Any microphone(s) assigned in this manner cannot be locked
out by any other microphone.
11. “Manual” mode can be selected at any time by pressing the Master
Volume control and observing the Manual/Auto mode indicator. In this
mode, the unit will behave like a conventional mixer (all automatic func-
tions are bypassed except for limiting and NOMA if selected). [10]
12. Adjust the Master Volume control for desired output level. This control is
at the last stage in the mixer signal chain, and does not affect microphone
gain, threshold setting, meter indication, monitor or direct outputs. [5]
13. Adjust the Threshold control as desired. If signal does not open the gates,
reduce threshold level. If undesirable sounds open the gates, increase
threshold level. [6]
5