Free Audio

Introduction

NDI Free Audio is an NDI utility that runs on all platforms and allows you to interface an audio device with NDI. This would for instance allow you to use a Raspberry Pi or similar cheap

compute devices as the world’s cheapest audio I/O device for IP audio; many of these devices have support for high quality audio connections1 which allows for professional quality audio over IP in ways that have truly never been possible before. When combined with the NDI Audio Direct audio plugins for all common digital audio workstations, one of the many NDI applications, or even Skype, Teams or Zoom. This will revolutionize the way audio is performed on the network.

This application supports any channel count and number of audio channels that are supported by your audio device. All NDI capabilities such as routing, discovery, floating point audio, WAN support are fully enabled.

Application

NDI Free audio is a command line tool that you can run on any device and should support all common audio interfaces on all operating systems, including Windows, Linux and Mac.

There is not an installer for the Mac due to the cost and time to make an installer for the Mac, which would require Apple's review. The Windows and Mac "installers" include a license click-through which requires the user to accept the NDI Free Audio EULA and why we don't have the application binary available for download. The binary is included in the Mac version of the NDI SDK.

When you run the application, it will provide you with a description of the options available and the list of audio devices on your system. For instance:

NDI Free Audio v5.0.0.0
Copyright (C)2014-2021, NewTek, inc.

Options:
-input "audio device name" or -input 1
or -input default
-input_name "Some Source"
-input_gain +10dB

-output "audio device name" or -output 3
or -output default
-output_name "My Computer (NDI-STREAM)"
-output_gain -15dB

Input Devices:
1 : Microphone (Jabra BIZ 2300) [default]
2 : FrontMic (Realtek High Definition Audio)
3 : Line (NewTek NDI Audio)
4 : Microphone (HuddleCamHD)

Output Devices:
1 :G276HL (NVIDIA High Definition Audio)
2 : Speakers (Jabra BIZ 2300) [default]
3 : Speakers (Realtek High Definition Audio)
4 : G276HL (NVIDIA High Definition Audio)
5 : Realtek Digital Output (Realtek High Definition Audio)

On raspberrypi

Audio Inputs

If you wish to receive audio from an input and turn it into NDI source you would specify the name of the audio device that you wish to use. For instance, you my use:

NDIFreeAudio.exe -input "Microphone (Jabra BIZ 2300) [default]"

Which will create an NDI output named “Free Audio” on the network. If you wish to specify the name of the NDI output, then you can simply provide it as follows.

NDIFreeAudio.exe -input "Microphone (Jabra BIZ 2300) [default]"

-input_name "My NDI Output"

One may use the audio input by list index with:

NDIFreeAudio.exe -input 2

If one wishes just to use the default audio device, then simply specify:

NDIFreeAudio.exe -input default

Finally, if one wishes to specify the audio gain on the device then one can provide this in decibel units:

NDIFreeAudio.exe -input default -input_gain +12dB

Audio Outputs

If you wish to take an NDI source and make it available on an audio output, you would specify the name of the audio device that you wish to use. It is of course then required that you specify the NDI source on the network that you wish to produce the audio from.

For instance, you my use:

NDIFreeAudio.exe -output "Speakers (Realtek High Definition Audio)"

-output_name "DRUNK (Test Patterns)"

One may use the audio output by list index with:

NDIFreeAudio.exe -output 4 -output_name "DRUNK (Test Patterns)"

If one wishes just to use the default audio device, then simply specify:

NDIFreeAudio.exe -output default -output_name "DRUNK (Test Patterns)"

Finally, if one wishes to specify the audio gain on the device then one can provide this in decibel units:

NDIFreeAudio.exe -output default -output_name "DRUNK (Test Patterns)"

-output_gain +12dB

Audio Inputs and Outputs

It is possible to use a single instance of this tool to run both audio input and output at the same time:

NDIFreeAudio.exe -output default -output_name "DRUNK (Test Patterns)"

-input default -input_name “My Source”

If one wishes to use multiple audio devices on your system at once, then you may simply run multiple separate application instances.

With the release of NDI 6.1.0 it will be available as a free standalone download. Additionally, there is added support for ASIO devices on Windows.