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Re: soundscape recording which mics

Subject: Re: soundscape recording which mics
From: madl74
Date: Sun May 25, 2014 1:25 pm ((PDT))
> Hello, Another recording, today,  this time with two mkh 30/30 in Faulkne=
r array.
>
>  140525T0600Z1001FAULKNER ARRAY, 12DB GAIN, HPF 250HZ https://soundcloud.=
com/freitojos/140525t0600z1001faulkner-array-12db-gain-hpf-250hz

Jose,

This was nowhere near the clarity of your last track. The birds were not
placed clearly in the sound image and the background sounded out of phase.=

The depth which I liked before was missing.

This shows well the difference between volume difference stereo and time
difference stereo. The ideal is the two combined, but most commercial stere=
o
is mixed with pan pots as volume difference stereo.

Theoretically anything full left or full right with a mic spacing of 200mm=

and a sample rate of 48KHz is shifted by about 28 samples. However, the ear=

has to have a sharp sound edge to detect this distance and most birdsong
does not have sharp enough edges.

The loud call in the recording sounded a bit to the left, but on analysing=

it, this was because it was about 3-4 dB louder on the left track. The
Faulkner array should have had equal levels on all incoming sounds, except=

for very close ones. Possibly some interaction with a windshield or
windshield affected the levels.

Even the best mics do not have flat frequency responses off-axis, even
before being fitted into a windshield, which adds internal reflections. Any=

spaced array will also have irregular responses off axis, but the ear is
tolerant to these. Don't spend big money on frequency responses. :-)

Try a 45-45 degree array with the two fig-8 mics 170 to 200 mm apart which=

will give you both volume stereo and time difference stereo. This is the
theory with the ORTF array.

David Brinicombe








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