SIP Audio Codecs

Connect between devices with Opus and


Remote Podcast Interview

NAB Show, Las Vegas


ipDTL for Radio Remotes

Capital FM, UK


Townsend Coleman - Voice Actor

In:Quality @ NAB Show, Las Vegas

Simulrec / Double-Ender / Tape-Sync

It can be called many different things depending on where you are in the world, or which area of audio / video production you are working.

Whatever you want to call it, here’s how it works…

  • Phone patch or SIP call established between interviewer and interviewee.
  • Local recording made of guest only.
  • Local recording made of host only.
  • Backup recording made, which is also useful for reference.
  • Recording of guest uploaded to internet or ftp server.
  • Both recordings are mixed/cut together, ready to be published.

Such recording methods have become far less common in recent years, with the advent of real time audio services such as ipDTL and the SIP Opus Codec.