John,
Apologies for labouring the point again but "fetch" is all about
acoustic perspective, not noise.
> narrow angled stereo using two cardioid Rode NT1A's with self-noise
> of 5dB;
No useable mic has an excess noise over thermal of 5dB. This figure is
claimed as a world record by B&K for one of their special
instrumentation mics.
Ill-defined noise figures are misleading. Sennheiser quote around 23dB
ITU-R468 weighting which many other mics can't get near.
I'd take the mic hiss down using my algorithm on Audacity unless it
sounded like part of the soundscape.
Now for the wildlife answer. :-)
> Let's say we are recording from the center of a meadow surrounded by
> trees and it is dawn on a spring morning and we are interested in a
> particular sound we can faintly hear in the distance.
What you don't quote is the acoustic background noise in the setup
like tree noise. Unless it is considerably lower than the faint sound,
you won't get much anyway. If it is faint to the ears, it will be
fainter to any mic.
None of this is what you are asking - so -
If the sound is faint to the ears it will be fainter to any mic rig.
What a good fetch gives is a closer perspective against the ambient
sounds and reverberation - if that is what the recordist wants.
What I would do is to listen to all three rigs and choose what sounds
best. I would probably choose the Jeklin simply because it used
Sennheiser mics which would survive rain. :-) Second would be the
crossed cardioids which will have a similar perspective at bird
frequencies, and avoid the hypercardiod with its annoying rear lobe
picking up tree noise from the rear. Two with two rear lobes would be
needed for stereo of course. If I could baffle off the rear
lobes, it may be useable, but the only hope of getting a "specimen"
recording would be with a rifle mic like the MKH-816 in mono.
The intervening trees would probably disperse the call. I spent a
summer trying to get a clean woodpecker drumming in my woodland on 150
metre cables. I could fetch it in at a reasonable level with rifle
mics, but the reverb from the trees muddled the drumming. I got the
blighter last year when it drummed on a tree across my car park at 60
metres using the fetch of my 416's.
http://www.stowford.org/recordings.htm#woodpeckerbeech
David
David Brinicombe
North Devon, UK
Cogito cogito ergo cogito sum - Ambrose Bierce
|