Dual-channel Voice Conference Recordings

With this change, the recording audio file of a conference will have two channels. The first channel of the Recording's media file contains the audio of the first Participant that joined the Conference. The second channel of the media file contains all other audio from the call.

With this release, when fetching the media file of a conference recording with the Recordings API, existing RequestedChannels query parameter can be used to specify whether the file should be downmixed to a single channel or downloaded as a dual-channel file. For backwards compatibility, when the RequestedChannels query parameter is not specified, the default download for Conference Recordings will be mono. See Public API documentation for additional information.

Prior to this release, the default behavior of Conference Recordings was limited to a mono recording, with all audio mixed into a single channel. While recording the individual call leg of a conference participant in mono or dual-channel continues to be available, this release makes it straightforward to obtain the recording of the whole conference in dual-channel, without the overhead of managing multiple recordings from the different conference’s call-legs. 

To use this feature, enable Dual-channel for Conference Recordings from the Voice Settings page in the Twilio Console. Please read the limitations below to understand the implications that enabling this setting may have on your application. 

• Not available for accounts using Encryption with Public Key. If encryption is enabled on the account, enabling dual-channel Conference Recording will have no effect (audio from a recorded Conference will be captured in a mono-channel file and encrypted as usual). 

• Not available for accounts using External Storage. If external storage is enabled on the account, opt-in for dual-channel will have no effect (audio from a recorded Conference will be captured in a mono-channel file and uploaded to the external AWS S3 bucket as usual). 

• Not available outside the US1 region. Conferences using the US1 region for processing and storage may be recorded in dual-channel. Using IE1 and AU1 regions for processing is not yet supported and Conference Recording will fail. See Regional Product Availability for more information.