O3A Virtual Microphone

Host Support

Audio

Controls

• Stereo Width
• Response

Description

The O3A Virtual Microphone extracts a stereo image from a 3D O3A mix using a front-facing "virtual" stereo microphone placed at the centre of the soundfield. The angle between the two capsules of this virtual microphone can be varied, along with their directional response. Available directional responses include omni, cardioid and figure-of-eight. This makes it possible to synthesise the results of various conventional coincident stereo recording techniques such as Blumlein X-Y and M/S.

This plugin does not allow you to point the front of the virtual microphone in other directions. If the front is not where you want, remember that you can rotate the soundfield using O3A Rotation or O3A Look.

This plugin actually only needs first order ambisonic information (and even then, the height channel is not used).

Be careful using this as a stereo decoder, because the overall output level can be highly dependent on source locations, as with the "real" recording techniques. You might wish to consider O3A Decoder - Stereo.

If you are interested in extracting sounds in particular directions from an O3A mix, you may also be interested in the sharper response of the O3A Beamer plugin.

The plugin is available in the O3A Core plugin library.

Controls

Control: Stereo Width

This is the angle between the two virtual microphones, between 0 and 180 degrees. For instance, 90 degrees should be used for Blumlein X-Y.

Control: Response

The response control determines the directional response of the two microphone capsules. Some useful values are:

For instance, 1.00 (figure-of-eight) should be used for Blumlein X-Y.

Presets

Presets are available for this plugin:

• Cardioids 130
• Cardioids 90
• Blumlein X/Y