25-Seven PDM II User manual

PDM II
PDM II User Manual
Front Panel Overview
Figure 1 - Front panel controls
The Input Level Meter (A) monitors the signal going into PDM II’s processing circuit. As they follow the A/D
converter in the signal path, they will accurately monitor the input regardless of the Input Sensitivity setting.
Note that this is a peak meter to be used as a diagnostic tool for setting input levels; it does not display RMS
voltage or a time-integrated level and is not intended to be a replacement for a more sophisticated loudness
meter.
Four dark LEDs: The input signal is below -36 dBFS.
One Green LED: The input signal is above -24dBFS.
Two Green LEDs: The input signal is above -18dBFS.
Three Green LEDs: The input signal is above -12dBFS.
Four Green LEDs: The input signal is above -6dBFS.
Top LED is Yellow: The input signal is above -0.5dBFS.
Top LED is Red: The input signal is above +0.5dBFS.
All LEDs are Yellow: The unit is expecting a Livewire input but not seeing a valid signal, or there is an
internal error.

The LCD display (B) shows a variety of information about the current status of the PDM II and provides a
menu system for front-panel setup and configuration.
The navigation cluster (C) is made up of left, right, up, and down arrows plus a green "checkmark" button
(generally used as an "Enter" button to confirm choices) and a red "X" button (used as a "Cancel" button to
exit a menu without saving any changes).
The main color-coded operational buttons are grouped together and their use in actual operation is outlined
in greater detail in the and sections, but in short: Front Panel Overview Basic Operation
The green Build button (D) starts building a delay at the start of a program.
The yellow Exit button (E) starts the process of exiting the delay to return to real-time audio.
The blue Cough button (F) temporarily stops incoming audio from reaching the delay buffer
The red Dump button (G) dumps the buffered audio or plays a pre-recorded audio file when a guest,
caller. or even the talent (!) utters something objectionable that should not be aired.
The Bypass button (H) is used for emergencies or when you want to electrically remove PDM II from the
signal path. Pressing it connects its outputs directly to its inputs with no processing or delay, and also clears
the PDM II's delay memory.
Note: PDM II also goes into electrical bypass - connecting the analog and AES/EBU RJ45 inputs
to the corresponding RJ45 outputs - when power is removed. In this situation, the PDM II becomes
a completely passive device with no level adjustment or A/D conversion taking place.
Rear Panel Overview
Figure 1 - Rear panel connections
The rear panel of the PDM II contains the following connections and information:

Analog Input and Output via RJ45 connector (A)
AES3 Input and Output via RJ45 connector (B)
GPIO on a standard DB15 connector (C)
Model number (D)
Serial number (E)
Primary and Secondary MAC addresses (F)
Secondary Ethernet port via RJ45 connector (G)
Primary Ethernet port via RJ45 connector; PoE-ready (H)
Chassis ground lug (I)
IEC AC power inlet (J)
Front Panel Menus
While PDM II offers a comprehensive HTML5 browser-based user interface, most of the setup, configuration,
and operation of the unit can also be accomplished via the front panel controls.
The front panel navigation cluster is made up of five buttons:
Navigation cluster
Left, Right, Up, and Down buttons, for navigating through lists and adjusting values; holding down an
arrow will generally repeat the action
Checkmark button, for entering menus and confirming choices
X button, to "Cancel" and exit a menu without saving any changes
To begin, press the Checkmark button to enter the top-level menu.
Configuration Menu
Pressing the Checkmark button from the normal status screen brings up the Configuration menu with sub-
menus for Audio, Controls, System, Network, GPIO, and Information.
The Up/Down arrows scroll vertically through the current menu. The Right arrow is used to enter any

available sub menus
Figure 1 - Configuration menu
Many of the PDM II's menus contain more than four items, and so cannot be completely displayed on one
screen. In this case, the extra items above or below the visible items (as indicated by the word "More") can
be seen by scrolling with Up/Down arrows.
For illustration purposes throughout this user manual, the screens will be merged into a single image so that
all information can be displayed at once.
The full configuration menu is below; the sections that follow will describe each sub-menu.
Figure 2 - Complete Configuration menu
Audio Menu
The Audio Menu is used to select and configure various audio I/O parameters and values.
Note - Some of the options displayed in the Audio Menu are contextual and will change
depending upon the type of audio input selected. Therefore, the figures below may not exactly
match what is available on the front panel of your unit.
Figure 1 - Audio menu

Audio Input
Audio input options include Analog, AES67, Livewire, and AES3. The up/down arrows scroll through the
options. In this and in subsequent edit screens, the Checkmark button accepts and applies any changes
while the X button cancels without saving.
Figure 2 - Audio input screen
AES67 Receive Channel
When using an AES67 audio source, the multicast address of the receive channel is set here. The up/down
arrows change the number by a value of 1, and the left/right arrows navigate between fields.
Figure 3 - AES67 receive address
Livewire Receive Channel
When using a Livewire audio source, the receive channel is set here. The up/down arrows change the
number by a value of 1, and the left/right arrows change the channel number by a value of 100.
Figure 4 - Livewire receive channel screen
Input Sensitivity
When using an analog audio source, this value should be set to the absolute loudest level PDM II will see in
your installation. The up/down arrows change the value. The "L" and "R" values represent the resulting
digital levels for the incoming analog signal and can be used along with an externally generated test tone to
adjust the sensitivity settings.

Figure 5 - Input sensitivity screen
For most installations where 0 VU = +4 dBu, the recommended setting is +14 dBu = 0 dBFS.
Note: Don't confuse dBu with dBFS!
dBu - an analog measurement - is a comparison to an arbitrary voltage. When a console's VU
meter reads 0, the output is typically +4 dBu, or 1.228 volts when using a sine wave. However,
actual audio levels are typically much higher due to audio peaks in the waveform. Analog audio is
very forgiving of such peaks, but digital audio is not.
A digital level of 0 dBFS (decibels in reference to full scale) is an absolute ceiling, and audio that
exceeds that level will result in audible distortion. PDM II has a built-in limiter to prevent levels
from exceeding 0 dBFS, but the recommended setting of 14 dBU = 0 dBFS provides 10dB of
headroom while still maintaining an 84dB signal-to-noise ratio. Lower settings can be used when
dealing with heavily processed input content, while higher settings may be necessary for content
with very wide dynamic range.
Analog Output Level
The Analog Output Level screen displays how the analog output level reflects digital audio levels within
PDM II's processor. With the setting as shown below, 0 dBFS within PDM II will yield a +14 dBu analog
output. The output levels should generally be set to match the Input Sensitivity level, though levels can be
adjusted to create a gain or loss at the analog outputs. Note that in Bypass mode, any such gain changes
are also bypassed and the output levels will equal the input levels.
Figure 6 - Output level screen
AES3 Default Output Rate
The default sample rate of the AES3 output can be set to 32, 44.1, or 48kHz.
Figure 7 - AES output rate screen
AES3 Output Lock
The sample rate of the AES3 output can be locked to the sample rate of the AES3 input, even if the unit is
not configured for an AES3 input. If there is no valid clock at the AES3 input, the output will revert to the rate
set in the AES3 Default Output Rate screen above.

Figure 8 - AES output lock screen
AoIP TX Type
Audio over IP (AoIP) audio can be sent from PDM II as either a standard AES67 stream or as a Livewire
stream. It can also be disabled if desired.
Figure 9 - AoIP Tx mode screen
AES67 Tx Address
The multicast address of the AES67 transmit channel is set here. The up/down arrows change the number
by a value of 1, and the left/right arrows navigate between fields.
Figure 10 - AES67 Tx address
Livewire TX Channel
The Livewire channel number for PDM II's audio output is set here. The up/down arrows change the number
by a value of 1, and the left/right arrows change the channel number by a value of 100.
Figure 11 - Livewire Tx channel screen

Controls Menu
The Controls menu is used to configure parameters and settings that determine how a delay is built, what
happens when the delay is dumped, and what happens when you exit the delay and return to passing real-
time audio.
Figure 1 - Controls screen
Dump Size
The Dump Size screen sets the amount of audio deleted when the Dump button is pressed. The up/down
arrows set a value between 1.0 and 60.0 seconds in 0.1 second increments.
Figure 2 - Dump size screen
Note - The Dump Size and Delay Size screens are not visible when the Dump Mode is set to
"OverKill."
Delay Size
The Delay Size control determines how much delayed audio PDM II will store in its buffer. The up/down
arrows set a value between a minimum of 1.0 second and the maximum as determined by the setting of the
Max Delay menu below.

Figure 3 - Delay size screen
Note: The Delay Size can also be temporarily set from outside of the menu system any time PDM
II is in Delay mode by pressing the left/right arrow keys to decrease/increase the value.
Max Delay
The Max Delay setting determines the upper limit of the Delay Size range described above to help prevent
operators from accidentally setting unrealistic delays. The maximum value is 90 seconds.
Figure 4- Max delay screen
Build Speed
The Build Speed screen sets how quickly PDM II can build up to and exit from its delay memory. The default
value is 7. Higher values will build the delay more quickly but may cause audible artifacts depending on the
type of programming.
As a rule, content with more density (such as highly-produced music) will better tolerate higher speeds
without audibly compromising the audio. More sparse material (such as speech) will more easily reveal
artifacts.
We recommend starting with the default value, carefully listening to your on-air audio during the build and
exit process, and making adjustments that balance the need to build a delay buffer quickly with your
tolerance for any variation in the audio quality during that time.
Figure 5 - Build speed screen
Max Speed
The Max Speed screen sets a limit for how quickly PDM II can build or exit a delay. The Build Speed setting
cannot be set faster than the value set here.

Figure 6 - Maximum speed screen
Build Mode
Build Mode determines the method PDM II uses to build its delay.
Figure 7 - Build mode screen
Expand - PDM II will send the incoming audio to the transmitter but at a subtly slowed-down rate, taking
more time until the delay memory is filled.
Insert - PDM II will play a station jingle, ID, or other fill material from its internal memory.
Pre-roll - PDM II will mute its output while you play material from another source, or while it signals your
automation system to play audio.
Build File
The Build File menu allows you to choose which audio file will play out from PDM II's internal memory when
building a delay using the "Insert" mode.
Figure 8 - Build file screen
Note: PDM II can store multiple audio files in its internal library. Files can be uploaded and
managed on the page of the web-based user interface.Audio Files
Note: The audio files should be stereo (or 2-channel mono) 16-bit WAV files with a 48kHz sample
rate to match the sample rate of PDM II's internal clock and ensure proper speed and pitch during
playback.
Exit Mode
The Exit Mode determines how PDM II behaves when transitioning between delayed and real-time audio.

Figure 9 - Exit mode screen
Compress - PDM II will play any remaining audio using time compression, subtly speeding up what's in
memory to rejoin real-time faster.
Roll Out - PDM II will stop adding audio to its buffer and play what's left in memory with no speed
changes. This sometimes referred to as the "wait and exit" mode.
Dump Mode
When the Dump button is pressed, PDM II can respond in one of two ways.
Figure 10 - Dump mode screen
Dump - In this mode, PDM II deletes the objectionable audio and "jumps ahead in time", then
immediately begins to rebuild its delay buffer.
OverKill™ - This mode plays a pre-selected file in place of the objectionable audio. In this mode, the
delay buffer is maintained and does not have to be rebuilt.
OverKill File
This menu allows you to select which previously uploaded audio file will play during a dump event when the
Dump Mode has been set to "OverKill."
Figure 11 - OverKill file screen
Note - When using OverKill mode, the Delay and Dump times are automatically adjusted to match
the length of the selected OverKill file and their corresponding controls will disappear from the
Control menu.

System Menu
The System Menu includes global system settings such as the date, time, and password as well as
hardware-specific settings such as the front panel brightness, contrast, and screensaver controls.
Figure 1 - System menu
Time Zone
When Network Time Protocol (NTP) is enabled, the Time Zone control selects a specific time offset for your
location. Four specific U.S. time zones (with and without Daylight Savings Time) are included along with all
internationally-supported offsets from Greenwich Mean Time (GMT).
Figure 1- Time zone screen
Time and Date
The current time and date can be set manually when NTP is not used. The left/right arrows change the field
while the up/down arrows change the value.
Figure 2 - Time and date screen
Note - Having an accurate clock is important when using PDM II's PD-Alert function which uses
date and time stamps to identify events and audio log files.

Time Format
Time format toggles between 12-hour (with AM/PM designations) and 24-hour ("military time") formats.
Figure 3- Time format screen
Password
The Password menu allows you to set and change the password required to access the web-based remote
control. The PDM II ships with no default password. You must set a password via the front panel in order
to access the unit remotely. The left/right arrows change the field while the up/down arrows change the
value. Valid characters include upper and lower case letters, numbers, and space between characters. Note
that spaces at the end of a character string are automatically removed.
Figure 4 - Password screen
If there is no password, the display will show a flashing "Web UI Disabled" message.
Note - PDM II passwords are designed to prevent unauthorized access via the remote network
interface and are visible from the front panel.
Brightness
The Brightness control adjusts the overall brightness of the front panel LCD.
Figure 5 - Brightness screen
Contrast
The Contrast control adjusts the contrast of the front panel LCD.

Figure 6- Contrast screen
Screen Saver
The Screen Saver control determines the length of time the front panel display stays on after the most recent
button press, from 1 to 100 minutes. Setting it to "Never" will keep the display on continually, although this is
not recommended due to the finite life of the LCD backlight.
Figure 7 - Screen saver screen
Network Menu
The Network Menu contains the controls necessary for configuring PDM II's two network ports. Note that not
all menu items will be visible with all configurations.
Figure 1 - Network menu
Networking Overview

PDM II contains two network interface controllers with rear-panel RJ45 Ethernet ports labeled "Primary" and
"Secondary".
The Primary port supports Power over Ethernet (PoE) and Livewire+/AES67. The Secondary port does not.
The Primary port is always active. The Secondary port can be disabled if desired.
Using DHCP v. Manually Assigning an IP Address
Only one port can support DHCP, DNS, and a specific Gateway at a time according to the table below:
Secondary
Port Enabled?
DHCP
Enabled?
Primary Port
Configuration
Secondary Port
Configuration
Yes Yes, on Secondary
User specifies IP
address and subnet
mask; no gateway or
DNS
DHCP server specifie
IP address, mask,
gateway, and DNS
Yes No
User specifies IP
address and subnet
mask; no gateway or
DNS
User specifies IP
address, mask,
gateway, and DNS
No Yes, on Primary
DHCP server specifies
IP address, subnet
mask, gateway, and
DNS
(Disabled)
No No
User specifies IP
address, mask,
gateway, and DNS
(Disabled)
By default, the Secondary port is disabled and the Primary port has DHCP enabled.
Separate Ports v. Using a Single Port
Generally speaking, and when two separate Ethernet ports are available, it is preferable to connect the
Primary port to the dedicated Livewire or AES67 network and the Secondary port to the "office" network for
remote access.
Separate Ports - In this scenario, both ports are enabled. The Primary port is used for AoIP (as the
Secondary port is not capable of handling Livewire or AES67 traffic). A user-specified IP address and
subnet mask are used, but there is no need for a gateway or DNS entries. The Secondary port is used to
establish a remote connection with an IP address and subnet mask either assigned manually or through
DHCP. Specific gateway and DNS settings can be entered. The two ports must be connected to different
networks.
Single Port - In this scenario, only the Primary port is enabled. Both AoIP traffic and the remote
connection are present on one port.

Primary DHCP Menu
If the Secondary port is disabled, DHCP on the Primary port can be toggled on or off in the Primary DHCP
menu.
Figure 1 - Primary DHCP enabled screen
When DHCP is disabled on the Primary port, its fields for manually setting the IP address, subnet mask, and
gateway are visible.
Secondary DHCP Menu
The Secondary port is disabled by default but can be toggled on in the Secondary Net Enable menu.
Figure 2 - Secondary DHCP enabled screen
When the Secondary port is enabled, it can be set to have DHCP enabled or disabled. When disabled, its
fields for manually setting the IP address, subnet mask, and gateway are visible.
NTP Enable Menu
NTP (Network Time Protocol) can be enabled or disabled in this menu.
Figure 3 - NTP enable screen
NTP Server Menu
This menu allows you to enter the IP address of a local NTP server. If no address is entered (the server is
set to 0.0.0.0), PDM II defaults to using "pool.ntp.org" servers.

Figure 4 - NTP server screen.
GPIO Menu
The GPIO menu allows you to program the hardware parallel inputs and outputs used to remotely control
certain PDM II functions. Livewire GPIO is configured in the Configuration page of the web-based user
interface.
Figure 1 - GPIO menu
The inputs and outputs are opto-isolated to easily interface with external equipment. A +5V supply and
ground are available on the DB-15 connector for simple remote controls using pushbuttons and LED status
readouts with a maximum total current draw of 200 mA. The supply is protected by an internal, self-resetting
thermal circuit breaker; should the breaker trip, power the unit off for several minutes to reset it.
Inputs require at least 6mA from the input common pin and the individual input circuit pin. Outputs can carry
up to 25 mA and up to 30VDC per channel between the output common pin and the individual output circuit
pin.
If the output signal is a pulse, its opto-isolator will turn on for 250ms. This can be adjusted to between 100ms
and 1000ms in the Configuration tab of the web GUI.
The pin-out of the DB-15 connector is as follows:
Pin Number Function
1 GPO 1
2 GPO 2
3 GPO 3
4 GPO 4
5 GPO 5
6 Not used
7 GPO Common
8 GPI Ground
9 GPI Power

10 GPI Common
11 GPI 1
12 GPI 2
13 GPI 3
14 GPI 4
15 GPI 5
GPIO Enable
Hardware GPIO can be enabled or disabled in the GPIO Enable menu. When enabled, the rear panel DB-
15 port is active.
Figure 2 - GPIO Enable menu
GPIO Inputs
Each of the five input pins can be assigned a PDM II function. The same function can be assigned to
multiple input pins.
Figure 3 - GPIO inputs
GPIO inputs can either be triggered or level-sensitive. Triggered (or edge-sensitive) inputs cause something
to happen when the input becomes active. Level-sensitive inputs cause a state to be true as long as the
input is active. The CueX and Bypass inputs are triggered; all others are level-sensitive.
Input functions include:
None: No function assigned.
Build: Front panel Build button.
Exit: Front panel Exit button.
Cough: Front panel Cough button.
Bypass: Front panel Bypass button.
CueX: Applies to Cue 1 through Cute 8 functions.
Cues are linked to incoming audio samples and stay with the sample regardless of how much time

manipulation is being applied, allowing them to be passed along to other devices.
Cue marks generate a 250ms trigger when they are reached.
Cues typically indicate important programming events such as commercials or news breakaways.
For example, if the network provides a contact closure to trigger a local break and its input is
assigned to a Cue function, PDM II will generate a corresponding Cue output when that sample is
reached in order to trigger external equipment to start the break.
Flag: Applies to Flag 1 through Flag 8 functions.
Like cues, flags also indicate an important programming event.
Flag marks record a continuous logic input, and their output reflects that logic state when the
appropriate audio sample reaches the PDM II's output
Flags can be used to activate a skimmer or logging recorder by connecting a mic's tally signal to the
input and using its output to keep the recorded turned on whenever the mic is open, regardless of
how much delay is used.
Utility: Applies to Utility 1 through Utility 4 functions. Allows you to have input closure immediately
cause and output closure with no delay. This is useful for implementing or diagnosing end-to-end relay
logic when connecting PDM II to other devices.
Pause: Suspends delay or exiting when active.
GPIO Outputs
Each of the five output pins can be assigned a PDM II function.
Figure 4 - GPIO outputs
GPIO outputs can either be triggered or level-sensitive. Triggered (or edge-sensitive) outputs emit a pulse
when something happens (the default pulse length is 250ms, but can be adjusted in the "Hardware GPIO"
section of the web UI Configuration page). Level-sensitive outputs indicate that a state is true as long as the
output is active. The CueX and various XXXTrig outputs are triggered; all others are level-sensitive.
Output functions include:
None: No function assigned
BuildTrig: A pulse indicating the delay has started building
FullTrig: A pulse indicating the delay buffer has become full.
DumpTrig: A pulse indicating a Dump has occurred.
EmptyTrig: A pulse indicating the delay buffer has been emptied.
Cue: Pulse from Cue 1 through Cute 8 functions. See the GPIO Inputs section for a full explanation of
Cues.
BuildLamp: Duplicates the front panel "Build" button lamp. Note that all "Lamp" pulses cause a "Low"

state when the lamp is on, a "High" state when the lamp is off, and cycles on and off when the lamp is
flashing.
ExitLamp: Duplicates the front panel "Exit" button lamp.
DumpLamp: Duplicates the front panel "Dump" button lamp.
CoughLamp: Duplicates the front panel "Cough" button lamp.
Bypass: Indicates the unit is currently in bypass.
Building: Indicates the unit is currently building a delay buffer.
Exiting: Indicates the unit is currently exiting delay.
DelayFull: Indicates the delay buffer is full and the maximum delay has been reached.
DelaySafe: Indicates there is a sufficient buffer for at least one delay dump.
DelayUnsafe: Indicates there is not enough audio in the buffer to perform a full delay dump.
DelayEmpty: Indicates the delay buffer is completely empty.
Muted: Indicates the unit is currently muted.
Flag: Applies to Flag 1 through Flag 8 functions. See the GPIO Inputs section for a full explanation of
Flags.
Util: Applies to Utility 1 through Utility 4 functions. See the GPIO Inputs section for a full explanation of
Utilities.
StreamFail: Indicates the currently-selected digital input has failed.
GPIO Test
The GPIO Test screen lets you verify that hardware GPIO connections and external remotes are properly
wired.
Figure 5 - GPIO Test menu
The "Ins" line shows the current input state of the five hardware GPIs. The "Outs" line allows you to set the
five hardware GPOs to any desired value.
Note - If the display shows "Disabled", then hardware GPIP is disabled. It can be enabled in the
. GPIO menu
When you leave the Test screen, all outputs will be restored to their configured values.