Trombones? Brass band? I thought this was a nature Recordist group? I have =
never maxed out my mics in nature after recording over well over 40000 hour=
s. As far as I know lightning makes no noise but thunder does. :)
Martyn
Martyn Stewart
Sent from my iPhone
Please excuse any spelling mistakes on this tiny keyboard.
www.naturesound.org
On Nov 1, 2010, at 4:34 PM, James Shatto <> wrote:
> 140SPL, because proximity can and will exceed that level. I've maxed out=
a 125dB SPL mic at 18" with a trombone. And I still had more to give. Pu=
t a group of 100 trombones in front of that mic and no good can come of it.=
With proximity. Even without proximity you'll have someone clapping with=
in a few feet of your mics. Maybe even some gun fire, door slams, screams =
of horror, and whatever mayham is modern life. Not quite a nature requirem=
ent, but a wolf howl at less than 5 yards? Lightning? Gun fire? A fallen=
tree? Or just a million plus insects, it all adds up. Even if no one sou=
rce is > 86dB (safe levels), when combined their chorus is deafening.
>
> And then there's the distortion factor. When mics operate at their limit=
s, they change character. Having higher limits makes them sound better at =
most sane levels IMO. Which is the main reason I got rid of my SM81's. Wi=
th a brass quintet, nice mics. With a brass band(40+ members), who replace=
d my mics with something not as good. Plus you can't have 110dB+ of dynami=
c range if your mics suck past 100dB. Not that noise floor means anything =
at those levels, but they can be reached in nature. Rock slide, volcano, .=
.. perhaps not an everyday thing, but it can and ultimately will happen. =
You only need it once to need it.
>
> - James
>
> --- On Mon, 11/1/10, Avocet <> wrote:
>
> From: Avocet <>
> Subject: Re: [Nature Recordists] Re: Binaural Upgrade
> To:
> Date: Monday, November 1, 2010, 4:51 PM
>
>
>
> Sorry folks I've just posted on this subject but I need to cooment on
>
> this quote which has just downloaded:
>
> > SPL limit >=3D 140dB
>
> > S/N =3D> 80dB +/- 10 (higher is better)
>
> > Self Noise <=3D 15dB +/- 10 (A weighted / lower is better)
>
> > Response =3D 20Hz-20kHz
>
> What on earth is being recorded at 140dBA? What mic input stage will
>
> handdle that? That's well into ear damage country. 90 dBs is very
>
> uncomfortable, 50 dB higher is 100,000 times that sound energy level.
>
> Your ear wax will be moving. (Not a recommended treatment)
>
> A S/N is relevant to a recording, not a transducer. With a background
>
> noise of 30dBs (quiet), That's a recording of a 110 dBA sound. For a
>
> loud natural sound at 90dBA, this is asking for a noise level of
>
> 10DbA. That simply can't be done technically with the very best pro
>
> gear.
>
> A-weighting doesn't help noise figures as the thermal Johnson noise of
>
> the air rises with frequency. That's the datum for self noise. BTW I
>
> heard it once as a young teenager in a windless grassland and after my
>
> ears had settled down for over an hour. My heartbeat was loud and I
>
> could hear my pulse and behind that was a very high hiss.
>
> Beware of frequency response figures that don't quote +/- limits.
>
> Beware of those which do, as the curves are frequently smoothed out.
>
> As I said in my last email, above all, trust your ears first.
>
> David
>
> David Brinicombe
>
> North Devon, UK
>
>
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