Setting up Rear Panel controls
Select the Rear Panel Ctrl Tab. The DM84 has 11
programmable inputs which can be used to control a wide variety of DM84
functions. Depending on the function assigned to them, these inputs may be
connected to momentary contact switches, toggle switches, or potentiometers.
When used with a switch, the inputs are activated by by connecting them to
ground through the switch contacts, called a "contact closure". When used with
a potentiometer, the inputs respond to the applied voltage, in the range 0 to 5
VDC.
Another feature of the rear panel control interface are a set of 8 programmable
outputs which can be set up to monitor audio input channel activity,
programmable input status, or whether or not particular presets are active.
Normally, a programmable output is inactive unless the
specified conditions are fulfilled, at which time it becomes active.
However, a programmable output can be inverted so that the
reverse is true - becoming active whenever the specified conditions are not
fulfilled, and vice versa. Programmable outputs act as an electronic "contact
closure" to ground. When the output is active, the contacts are closed
(conducting to ground), when inactive they are open.
An important application of the rear panel control interface is to manage what
is called the rear panel gain for input and output audio channels. This
is an additional gain value that is added to the "main" gain value for a
channel to give the total gain applied. Rear panel gain may be adjusted over
the range -60dB to 0dB, or set to "Off" to silence the channel. It is intended
to function as a variable attenuator for the audio channel. The purpose
is to allow some amount of gain or level control by the end user in a safe
manner, using one of the programmable inputs. A typical application of rear
panel gain is to allow adjustment of the level of an audio output (driving a
speaker) downward from some maximum by means of turning a potentiometer
connected to a programmable input which has been set up to use the
Analog Output RP Gain Control
function described below.
This tab contains a notebook with two pages, one for programmable input setup
and one for programmable output setup. If connected to a DM84, changes made in
this tab take effect immediately. As always, the changes are not permanent
unless the DM84 settings are stored to a preset in nonvolatile memory.
The rear panel control settings (ALL of them, as a group) can be
copied and pasted into another preset.
The first tab along the bottom of the rear panel control notebook
is used to select the programmable inputs page. On this page the following
controls and indicators are always visible:
Here is a view of the Rear Panel Ctrl Tab with the programmable
inputs page selected:

The second tab along the bottom of the rear panel control notebook
is used to select the programmable outputs page. On this page the following
controls and indicators are always visible:
Here is a view of the Rear Panel Ctrl Tab with the programmable
outputs page selected:

Programmable inputs notebook
Settings for the 11 programmable inputs are contained within a notebook, with
one page per programmable input. The tabs along the bottom of the notebook are
used to select one of the programmable inputs for setup.
To set up one of the programmable inputs, select a function type from the Function
list. Once selected, controls appear which are used to choose the specific
feature or features of the DM84 that the function applies to. These choices
will vary according to the nature of the programmable input function values.
The following function types are available:
-
Analog Input RP Gain Control (AI) This function
controls the rear panel gain of one or more audio inputs in response to
changes in voltage applied to the programmable input. Normally this
function is used by connecting the wiper of a potentiometer to the programmable
input so that it acts as a "volume control" for the audio input channels that
the function applies to. The voltage may vary from 0 to 5 VDC. The range over
which the gain of the audio input channels is allowed to vary is controlled by
the Rear panel input gain controls
described below. This function can be applied to any combination of audio input
channels.
-
Inc Input RP Gain 1dB (II) This function
increments the rear panel gain of one or more audio inputs in response
to a contact closure. This is normally used with a momentary contact switch.
The range over which the gain of the audio input channels is allowed to vary is
controlled by the Rear panel input gain controls
described below. This function can be applied to any combination of audio input
channels.
-
Dec Input RP Gain 1dB (DI) This function
decrements the rear panel gain of one or more audio inputs in response
to a contact closure. This is normally used with a momentary contact switch.
The range over which the gain of the audio input channels is allowed to vary is
controlled by the Rear panel input gain controls
described below. This function can be applied to any combination of audio input
channels.
-
Analog Output RP Gain Control (AO) This
function controls the rear panel gain of one or more audio outputs in
response to changes in voltage applied to the programmable input.
Normally this function is used by connecting the wiper of a potentiometer to
the programmable input so that it acts as a "volume control" for the audio
output channels that the function applies to. The voltage may vary from 0 to 5
VDC. The range over which the gain of the audio output channels is allowed to
vary is controlled by the Rear panel output gain controls
described below. This function can be applied to any combination of audio
output channels.
-
Inc Output RP Gain 1dB (IO) This function
increments the rear panel gain of one or more audio outputs in response
to a contact closure. This is normally used with a momentary contact switch.
The range over which the gain of the audio output channels is allowed to vary
is controlled by the Rear panel output gain controls
described below. This function can be applied to any combination of audio
output channels.
-
Dec Output RP Gain 1dB (DO) This function
decrements the rear panel gain of one or more audio outputs in response
to a contact closure. This is normally used with a momentary contact switch.
The range over which the gain of the audio output channels is allowed to vary
is controlled by the Rear panel output gain controls
described below. This function can be applied to any combination of audio
output channels.
-
Recall Memory Preset (MP) This function
initiates the loading of a memory preset in response to a contact closure. This
is normally used with a momentary contact switch, and can be applied to any one
of the memory presets stored in the DM84 memory.
-
Toggle Mute Inputs (MI)
This function toggles the mute status of one or more audio inputs in response
to a contact closure. If muted, a contact closure unmutes the channel, and vice
versa. This is normally used with a momentary contact switch, and can be
applied to any combination of audio input channels.
-
Toggle Mute Outputs (MO)
This function toggles the mute status of one or more audio outputs in response
to a contact closure. If muted, a contact closure unmutes the channel, and vice
versa. This is normally used with a momentary contact switch, and can be
applied to any combination of audio output channels.
-
Toggle Mute Crosspoints (MX) This function
toggles the mute status of one or more matrix crosspoints in response to a
contact closure. If muted, a contact closure unmutes the crosspoint, and vice
versa. This is normally used with a momentary contact switch, and can be
applied to any combination of matrix crosspoints associated with one
particular audio input channel.
-
Momentary Mute Inputs (MMI) This function
momentarily mutes one or more audio inputs in response to a contact closure.
The channel is muted when the contact closure is made, and unmuted when it is
broken. Normally used with a momentary contact switch, either a "push to mute"
or a "push to talk" action can be supported (depending on whether a normally
open or normally closed
switch is used). This function can be applied to any combination of audio input
channels.
-
Momentary Mute Outputs (MMO) This function
momentarily mutes one or more audio outputs in response to a contact closure.
The channel is muted when the contact closure is made, and unmuted when it is
broken. Normally used with a momentary contact switch, either a "push to mute"
or a "push to talk" action can be supported (depending on whether a normally
open or normally closed
switch is used). This function can be applied to any combination of audio
output channels.
-
Momentary Mute Crosspoints (MMX) This function
momentarily mutes one or more audio outputs in response to a contact closure.
The channel is muted when the contact closure is made, and unmuted when it is
broken. Normally used with a momentary contact switch, either a "push to mute"
or a "push to talk" action can be supported (depending on whether a normally
open or normally closed switch is used). This
function can be applied to any combination of matrix crosspoints associated
with one
particular audio input channel.
-
Run a Macro on Close (RM) This function
initiates the running of a macro in response to a contact closure. This is
normally used with a momentary contact switch, and can be applied to any one
of the macros stored in the DM84 memory.
-
Run a Macro on Close/Open (RM2) This function
initiates the running of a macro in response to a contact closure, and another
macro in response to the subsequent contact opening. This is normally used with
a momentary contact switch, and can be applied to any two
of the macros stored in the DM84 memory.
-
Momentary Unmute Inputs (PTT) This function
momentarily unmutes one or more audio inputs in response to a contact closure.
The channel is unmuted when the contact closure is made, and muted when it is
broken. Normally used with a momentary contact switch, either a "push to talk"
or a "push to mute" action can be supported (depending on whether a normally
open or normally closed switch is used). This
function can be applied to any combination of audio input channels.
When certain functions have been selected and the control panel is connected to
a DM84, the Test button is enabled. Pressing this button simulates a
contact closure on the programmable input and is very useful for testing the
function.
Programmable input status indicators
These display the status of the corresponding programmable input when a function
has been assigned and the control panel is connected to a DM84. For the
Analog Gain Control functions, the indicator is lit red when the voltage
applied to the input is in the upper half of the allowable 0 to 5VDC range. For
all other functions, the indicator is lit red when a contact closure
occurs.
Rear panel input gain controls
These are used to set up rear panel gain control for input channels. This
operates as an attenuator, adjustable from some minimum gain (max attenuation)
up to 0dB (no attenuation). There are two parameters:
-
The gain preset
value establishes the starting point for rear panel gain control on system
powerup. This normally used to select a gain point somewhere in the middle of
the adjustment range. The user may then adjust gain up or down from there.
-
The minimum gain value establishes the bottom end of the rear panel gain
control range.
The group consists of these numerical controls and indicators:
-
Gain Preset - The gain preset value is displayed here and can be
adjusted from -60dB to 0dB, or set to "Off". There are two ways to change the
value:
-
Click on the buttons next to the control to run the value up or down
-
Type a value directly into the control and press ENTER
-
Min Gain - The mimimum gain value is displayed here and can be adjusted
from "Off" up to the gain preset value. This value tracks the gain preset value
and is automatically adjusted as required to satisfy the rule:
-
minimum gain <= gain preset
The value may be changed in the same manner as the Gain Preset control.
-
Rear Panel Gain - these read-only indicators display the current rear
panel gain setting (in dB) for each audio input channel. These are useful for
monitoring the effects of rear panel control actions.
Rear panel output gain controls
These are used to set the range over which the rear panel gain of an
output channel can be adjusted by certain programmable input functions. These
function in the same manner as the Rear panel input gain
controls described above.
Programmable outputs notebook
Settings for the 8 programmable outputs are contained within a notebook, with
one page per programmable output. The tabs along the bottom of the notebook are
used to select one of the programmable outputs for setup.
To set up one of the programmable outputs, select a function type from the Function
list. Once selected, controls appear which are used to choose the specific
feature or features of the DM84 that the function applies to. These choices
will vary according to the nature of the programmable output function values.
The following function types are available:
To finish the setup, the programmable output invert status may
be set using the Invert checkbox. If inverted, a programmable
output will behave in a manner opposite to that described above in the function
descriptions.
Programmable output status indicators
These are lit red when the corresponding programmable output becomes
active (conducting to ground).
Channel activity controls
When the Monitor Input Ch Activity function is
assigned to a programmable output, these are used to set the parameters
controlling the time response of the function:
-
input qualification time
- the length of time that an audio input must be dominant before the
programmable output is activated.
-
output hold time - the length of time after an audio input has ceased to
be dominant before the programmable output is deactivated.
The group consists of two numerical controls:
-
Input Qualification Time - The qualification time value is displayed
here and can be adjusted from 0.1 to 25.5 seconds. There are two ways to change
the value:
-
Click on the buttons next to the control to run the value up or down
-
Type a value directly into the control and press ENTER
-
Output Hold Time - The hold time value is displayed here and can be
adjusted from 0.1 to 25.5 seconds. The value may be changed in the same manner
as the Input Qualification Time control.
Rear Panel Ctrl Copy/Paste
The entire group of rear panel control settings can be copied and pasted
into another preset. This can save a lot of time when a common rear panel setup
needs to be duplicated in multiple presets. There are two ways to do this:
-
Right click somewhere outside the programmable inputs/outputs notebook
and choose Copy ALL Rear Panel Ctrl Settings from the popup menu. Then
load the destination preset from file (or recall it from device memory), right
click somewhere outside the programmable inputs/outputs notebook, and choose Paste
ALL Rear Panel Ctrl Settings
from the popup menu.
-
Choose Edit->Copy ALL Rear Panel Ctrl Settings from the Menu Bar.
Then load the destination preset from file (or recall it from device memory),
and choose Edit->Paste Rear Panel Ctrl Settings from the Menu Bar.
Copyright © 2006 Lectrosonics, Inc.