Recording with TetraMic, etc

Using the TetraMic

The TetraMic is a tetrahedral soundfield microphone made by Core Sound, and I have described it in detail elsewhere on this site.  The microphone does not include electronics to process the output from the capsules (known as A-format) into the B-format that is used for storage and processing, so this has to be done by computer, either live while recording or later in post-processing.

When I first received the TetraMic (in 2007), I continued to use the same equipment for recording as I had been doing with my native B-format setup; I merely added the conversion from A- to B-format to my workflow in place of the alignment procedures that were necessary previously (the conversion uses a customised parameter file supplied by Core Sound, which makes all the necessary corrections for the particular set of capsules).

Since 2011 I have been using a Tascam DR-680 recorder, which is quicker and easier to set up, although there are no sensible monitoring facilities.

Other microphones

In addition to my TetraMic I also have a Brahma microphone and a SoundField SPS200.  Either of these can be recorded using the Tascam DR-680 in the same way as the TetraMic and the recordings then processed later similarly.  Of course, the Brahma and SoundField each come with their own processing software, though only the Brahma is individually calibrated.  I had my Soundfield SPS200 calibrated by Core Sound, so I can process its outputs using the same software as I use for the TetraMic.  The latest encoding software from VVAudio, VVEncode, can accept the Brahma calibration files as well as Core Sound's, so I can use the same workflow with any of the three microphones.

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