Adding Audio Messages to Noise Cancelling Intercoms

By: Tim Bruxvoort

Articles

Pre-recorded audio messages can be uploaded directly to the TCIS-2 or TCIV-2 IP Stations and triggered automatically by specific station events. Files are uploaded through the station’s web interface, which also displays available storage and allows file management.

Audio File Requirements

WAV format
PCM, 16-bit
16 kHz sample rate
Mono (single channel)

Storage & File Limits

Total storage capacity: 20 MB (shared across all files)
Maximum filename length: 50 characters
Any number of files may be uploaded, provided the total size remains within the 20 MB limit

Event Configuration

Up to 15 unique events can be configured to trigger audio playback

This functionality enables reliable, automated delivery of announcements, instructions, or alerts based on real-time activity at the station.

Uploading audio files:

Log into the IP Station
Select Edge Configuration > Audio Messages.
Browse to the desired audio file, and press Upload. The file will now appear in the list of audio files

Play Message Settings

The audio message playback can be triggered by the following main events:

DTMF
Call
Relay

Play Message on DTMF

An audio message can be triggered during an active call when specific DTMF tones are received. Supported digits include 0–9, * and #. This event can also be filtered by directory number (SIP ID), allowing playback only when tones are received from designated endpoints.

In the example below, the audio file “ringcd.wav” is played when the station detects DTMF digit 3 during a call—meaning the remote party presses 3 on their keypad.

The call must be fully established before the DTMF digit is sent; otherwise, the message will not be triggered. The audio will play once and is mixed into the live conversation.

Play Message on Call Events

Audio messages can be triggered based on call activity, including incoming, outgoing, or both directions. Playback can also be filtered by directory number (SIP ID) or by Ringlist calls (ringlist0, ringlist1, ringlist2).

Supported Call Events

Call Ringing: An incoming or outgoing call is present on the IP station (no auto-answer)
Call Accepted: An incoming or outgoing call has been answered
Call Ended: A call has been terminated, hung up, or cancelled
Group Accepted: An outgoing group call from the IP station has been established
Call Queued: An outgoing call has been placed in a queue on the Master station
On Hold: A call has been placed on hold by a remote Master station
Transferred: A call has been transferred by a remote Master station to a third station; the IP station rings (no auto-answer). A message such as “Your call has been transferred, please wait…” can be played. This event is not triggered on the Master station that initiated the transfer
Call Setup Failed: The message is played if a call button or input is activated while the station is offline

Playback Options

One Time: The message plays once, then stops
Repeat: The message repeats at a configurable interval until the call event ends
File Then Tone: The message plays once, followed by the standard ringing tone

This functionality allows precise control over when and how audio messages are delivered during different stages of a call.

Custom Ring Message

When the intercom button is pressed, or a sensor connected to a switch input is triggered, the system can be programmed to play a reassurance message (e.g., “Calling scale operator, please wait”) while the receiving station is ringing and awaiting an answer. You can program the message to repeat to ensure the visitor hears the full message.

Audio Message Routing

The audio message can be routed to:

Speaker, or
Speaker & Mic

The audio message is always played through the loudspeaker of the calling station. Optionally, it can also be transmitted as a “Microphone” signal, allowing the message to be heard by the remote party during an active call.

This feature is useful for identifying the calling station. For example, in facilities with multiple truck scale lanes, a message such as “Scale 1” can clearly indicate which location is initiating the call.

When the “Speaker & Mic” option is enabled, the calling station’s microphone is temporarily muted while the message is playing. Normal microphone operation resumes automatically once playback is complete.

Play message on Relay

An audio message can be triggered when a relay or output changes state, including On, Off, Slow Blink, or Fast Blink.

For example, when the relay on a door station is activated, the system can play a message such as “The door is open, please enter.” The message is played once and is mixed into the active conversation audio.

Applications and Use Cases

Accessible Door Intercom Operation

A visitor initiates a call by pressing the button on the door intercom. The operator station rings, while a continuous local message reassures the visitor: “Your call is in progress, please wait.” Once the operator answers, two-way communication is established. The operator can then unlock the door by sending a DTMF command (e.g., “6”) and end the call.

At that point, a local message confirms access: “The door is now open, please enter the building. Have a nice day.” After 20 seconds, the door automatically closes, followed by a final message: “The door is now closed. Please use the call button to speak with an operator.”

If the operator is temporarily unavailable, the system keeps the visitor informed:

Call on hold: A continuous message plays: “Your call is on hold, please wait.” The operator can resume the call at any time.
Operator busy (call queued): A continuous message plays: “Your call is registered, but the operator is currently busy. Your call will be answered as soon as possible. Please wait.”

Automatic Local Messaging from Master Station

The system also provides automated status updates for calls handled through a master station:

Queued call: When an outgoing call from an IP substation is queued, a continuous message plays: “Your call is in progress, but the operator is currently busy. Your call will be answered as soon as possible. Please wait.”
Call on hold: If the call is placed on hold, the substation plays: “Your call is on hold, please wait.”
Call transfer: When the call is transferred to another station and is ringing (without auto-answer), the substation plays: “Your call is being transferred, please wait.”

These automated announcements ensure users are consistently informed of their call status, improving usability and accessibility.