Don't call it tetramic. It will upset len Moskowitz. I use a process developed by Angelo Farina's team, using Matlab scripts. Initially, I was given permission only to use it, but not share it, but a few months ago, Angelo said I can forward the scripts to Marc Lavallee, who is modifying them to run on Octave. Octave is a free program, and these scripts will be released to public, so it should be possible for anyone who builds a tetrahedral microphone to calibrate it and generate filtermatrix files. These files can be used with VVEncode (purchased) or X-volver (free) to produce B format files. In the meantime, I am willing to create filtermatrix files for anyone who wants to do their own measurements. (Fons will also do it, but mostly he does it for Linux) You do not need an anechoic chamber. You need a space with the first reflection atleast 2.5 metres away. A room with a five meter high ceiling and dimensions of 7.5 meters by 5 meters will be adequate. You can use Angelo's inverse sine sweep. I will describe my process in detail if you wish, but I am very happy with the imaging I am getting with Brahma microphones. The tetrahedral structure printed by Shapeways is very accurate, and that helps too.
Umashankar Don't use sennheiser's generic filters. Their capsules are also 14 mm, but they are spaced much further apart (mine are almost at the theoretical minimum). At the AES, the Sennheiser booth was next to Brahma, and many people compared the imaging of the two. Umashankar Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows 10 From: Bo-Erik Sandholm<mailto:bosses...@gmail.com> Sent: Tuesday, January 3, 2017 11:29 AM To: sursound<mailto:sursound@music.vt.edu>; glard...@iol.ie<mailto:glard...@iol.ie> Subject: Re: [Sursound] [allowed] brahma Good luck in your continued effekt. By the way, i have accuired one of your Tetra mic 3d shapeway for 14 mm capsules. I have not yet assembler it. I Wonder is there any software package and description on How to create calibration files for The mic? I will probably have The possibility to get temporary access to a anechoic room. In worst case i Will use the generic calibration from sennheiser :-) The mechanical size of The tetraeder is about right. Bo-Erik Den 2 jan. 2017 9:01 em skrev "Gerard Lardner" <glard...@iol.ie>: > Sorry to hear of the falling-out. I have had some issues with the > build-quality of my Brahma, which was made by Embrace Video, but > nevertheless it remains my 'go-to' mic for choral recording. > > With best wishes for 2017, and for your ongoing Ambisonic microphone > projects, > > Gerard > > > On 02/01/2017 06:57, umashankar manthravadi wrote: > >> This is just an announcement that Nakul Sood and Embrace video will no >> longer be manufacturing or selling Brahma ambisonic microphones. Our very >> informal arrangement has come to an end as Nakul Sood demanded 1)I hand >> over complete technology and manufacturing protocols, 2) sign a >> non-disclosure agreement and 3) sign a non-compete agreement. (there were >> other demands) I have always worked on Brahma as a shared project, with >> help from many people and I have no desire to sign a non-disclosure >> agreement. >> >> I had made atleast 20 Brahma microphones before this project began, and I >> will continue to make one off brahmas as demanded (I am currently making >> five second order microphones for Angelo Farina) and I am setting up fairly >> high tech processes in Bangalore where I now live (laser cut microphone >> bodies!) >> >> Umashankar >> >> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: <https://mail.music.vt.edu/mailman/private/sursound/attachme > nts/20170102/572ce57e/attachment.html> > _______________________________________________ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, > edit account or options, view archives and so on. > -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20170103/f956a4dd/attachment.html> _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on. -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20170103/c84d0caa/attachment.html> _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
