TJ&LJ [naturerecordists] writes:
> Thanks David, looks interesting. =C2=A0Did you buy the mics in that $30 b=
udget or did you get capsules and wire them up yourself?Regards,
TJ,
The mics *were* the budget. I bought several of these discounted mics from=
Canford Audio in the UK. They were lapel mics with 3.5mm plugs and I got
them for experimenting. The cardboard box was a tryout and when I get aroun=
d
to it I'll make a plastic version. The box has to be non-resonant and I
taped stiff plastic foam across the back for this.
As in the web page, the principle is a rectangular horn. A sound entering
the horn will effectively reflect 180 degrees and not resonate as happens
with most horns. I measured about 12 dB gain over free air which helps to
get over the mic hiss with cheap mics.
The brinibox object angle is wider than the crossed gunmics and I think it=
gets a cleaner stereo image.
The joy if this rig is simplicity. It's not trendy or fashionable but it
gives good results. It should give even better results with quality mics an=
d
I publicised the design hoping that other recordists would improve on it. I=
don't believe that the basic design is patentable, and the idea is to make=
it free for experimenters.
For the recordings, I wrapped fine net curtain material over it as a
windshield. It's large and looks strange but it works. :-)
What is important is that the horn edges should be sealed and the mics
fitted with no gaps so that the high pressure zone at the throat of the hor=
n
doesn't leak out.
David Brinicombe
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