dear all i am the person who makes brahma microphones. the photographs and description on the oomagamma site are of one early version. the capsules are cardioid 14 mm, mounted on a drilled out sphere. (it was not very successful.) while oomagamma sells some of the microphones i had made, brahma is not one of them. that is because as it stands, i am not providing calibration files or software, so it cannot be a truly commercial venture. for almost a year now, i have been making my parts using shapeways, so it is now possible for me to make accurate assemblies using a variety of capsules from 6 mm onwards. the capsules are cardioids, an the arrangement a tetrahedron. most of my recent experiments have been on mounting the capsule assembly inside a metal mesh sphere, now internallly shockmounted. this is because i realise the real limitation of many of the tetrahedral microphones around is their susceptibility to wind, electrical interference and handling noises. there is no poi nt making a perfect microphone if every recording i make is vitiated by noises! i have made half a dozen of these microphnes so far this year (all 14 mm) along with modified zoom H2 recorders. but my next brahma microphone is going to use large (25 mm) capsules and is meant to be an upgrade in terms of audio quality. that means phantom power and balanced outputs as an option. all the shapeways parts i have designed for brahma are available for purchase from shapeways.com. i will help which ever way i can for those who want to make their own. i have posted a photo essay on the zoom H 2 modification and can provide links. i would like to encourage people to make their own. i will of course build one for anyone who wants it, but as i have said before, they will have to figure how they will calibrate the microphone. there is brahmavolver a free program produced by angelo farina's group for the original 14 mm brahma kits i had made for aida. (there were ten of them). it is also possible to buy a fuly calibrated brahma from AIDA, which is part of Angelo Farina's university i have posted links to files on skydrive. the folder called ambisonics has recordings using six mm capsules. the one called brahma 140 has recordings made by hector centano, who is a member of this group. he measured his brahma and sent the files to fons adriansen, who created calibration files to be used with tetraproc softare. umashankar
i have published my poems. read (or buy) at http://stores.lulu.com/umashankar > Date: Mon, 11 Jul 2011 20:54:27 +0100 > From: [email protected] > To: [email protected] > Subject: Re: [Sursound] Opinions on the Brahma soundfield mic kit > > Has anyone done any A/B comparisons of the Brahma with other mics such as > the tetra mic and the STS200? > > I'd love to hear the results of a 'soundfield' mic shootout. > > > > On 11/07/2011 20:00, "Eric Benjamin" <[email protected]> wrote: > > >Dan Andrew > >> whats the catch? > > > >I'm not sure that there is a catch, as such. > > > >It's apparent that the Brahma is an 'A-format' microphone, in which it is > >the > >capsule signals that are recorded and not the Ambisonic B-format. To get > >B-format will require some matrix processing (sum and difference of > >capsule > >signals), and some equalization to restore flat frequency response. Not > >only > >that, but the microphone array appears to be made up of omnidirectional > >signals > >which means that the difference signals (B-format X, Y, and Z) will need > >to have > >the low frequencies boosted substantially to give any semblance of flat > >frequency response. > > > >Perhaps the Oomagamma folks can supply some commentary, and much better > >than > >that, perhaps they can supply some A-format demonstration files. > > > > > > > > > >----- Original Message ---- > >From: Dan Andrews <[email protected]> > >To: Surround Sound discussion group <[email protected]> > >Sent: Mon, July 11, 2011 4:36:34 AM > >Subject: [Sursound] Opinions on the Brahma soundfield mic kit > > > >Im looking to buy a mic for b-format recording and wondered if anyone on > >the > >mailing list has had any experience with Brahma soundfield mic kit? > > > >http://www.oomagamma.com/brahma_kit/brahma_kit.html > > > >This kit includes the mic, a modified 4ch Zoom 24/96 recorder, cables, a > >shockmount, 2 wind shields and a wooden case to put it all in, all for 729 > >euro!!!! > > > >This all seems far to good to be true, whats the catch? > > > >All the best > > > >Dan > > > > > >-------------- next part -------------- > >An HTML attachment was scrubbed... > >URL: > ><https://mail.music.vt.edu/mailman/private/sursound/attachments/20110711/4 > >2815fb6/attachment.html> > > > >_______________________________________________ > >Sursound mailing list > >[email protected] > >https://mail.music.vt.edu/mailman/listinfo/sursound > > > >_______________________________________________ > >Sursound mailing list > >[email protected] > >https://mail.music.vt.edu/mailman/listinfo/sursound > > > _______________________________________________ > Sursound mailing list > [email protected] > https://mail.music.vt.edu/mailman/listinfo/sursound -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20110712/13d384fc/attachment.html> _______________________________________________ Sursound mailing list [email protected] https://mail.music.vt.edu/mailman/listinfo/sursound
