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2. Re: sanken cuw-180 recording

Subject: 2. Re: sanken cuw-180 recording
From: "Jez" tempjez
Date: Wed Jun 20, 2012 4:55 am ((PDT))
what I do sometime find rather amusing is that, especially on some of the e=
ven more tech-nerd forums out there, some folks seem to be so obsessed with=
 the specs of their mics & then use them to produce terrible music & proces=
s / eq the heck out of their recordings anyway.

all that really matters is how the mics sound & how well we listen & for th=
ose things there are no specs possible or useful.

--- In  Gregory O'Drobinak <=
.> wrote:
> Gentle people:
> The A-law issue is actually more complex than just 'levels'.
> One=C2=A0issue here is that there are quite possibly an infinite number o=
f shaped
> noise spectra that can register as the same A-law level. So if the self n=
oise of
> the mic is measured as being 16 dBA, the noise spectrum of that mic=C2=A0=
could favor
> the low, the mids or the highs and still be read by the sound level meter=
 as 16
> dBA.
> The Fletcher-Munson study that gave rise to the 40 phon (in level) A-law =
> was done a long time ago and was=C2=A0formulated to account for the perce=
ption of
> individual tones, not random noise, back in 1933. Go to the audiologist
> and=C2=A0that's what you get: tones to test your hearing, not=C2=A0even b=
> noise!=C2=A0
> In particular, A-law weighting of low-level background noise (such as the=
> of the city) does NOT correlate at all well with what most people hear, i=
> devalues=C2=A0the low end perception of the spectrum=C2=A0severely. And A=
-law weighting
> does not account for our enhanced perception of low-level noise at=C2=A0a=
round 6=C2=A0KHz;
> it devalues it by 10 - 12 dB. That is why the BBC and others did the rese=
arch to
> account for this perception and=C2=A0formulated the ITU-R 468 spec. Note =
that this
> spec specifies not only the weighting curve, but also the precise method =
> metering (measuring) the level=C2=A0of the noise.
> ITU-R 468 is better (and much newer!) science, not an attempt to hammer
> something into a 'compartment' in which it does not belong.
> Here are some links:
> (look towards the =
end for
> different weighting filters)
> I can see why Jez has an issue with A-law specs for mic self-noise. But i=
> 468 the be-all and end-all spec? For some people, maybe not, for their ow=
> perception may be heightened or stunted in ways different from the 'norm'=
 of the
> human population. But I do believe that applying A-law curve, which was d=
> for the perception of tones, is not applicable to measuring noise in
> any=C2=A0reasonable way. Why folks continue to apply it to such purposes =
is quite
> puzzling. Perhaps they didn't know before ( in the '60s) what we know now=
> there is just too much inertia to move away from A-law. It's sad that the=
> manufacturers haven't kept up with current perception theory and measurem=
> methodology.
> Human perception, especially hearing, is quite complex. Pick up a contemp=
> psychoacoustics text and you'll see.
> ITU-R 468 is much better than A-law for self-noise measurement, but it's =
> an approximation to what really happens in our minds when we listen to no=
ise and
> make our own judgements about it.
> So what do we do now?=C2=A0 :>}
> Numbers can lie. I suggest we listen and make more comparison recordings =
> different mics on a common (good) recorder under identical extremely quie=
> conditions. And by identical, I mean not only the same background level, =
> with the preamp gain calibrated to give the same output level for each mi=
> according to a properly chosen calibration tone. Then we can make our own=

> judgements independently from the vendor's 'spec' sheets.
> Let's move forward.
> - Greg
> ________________________________
> From: Dan Dugan <>
> To: 
> Sent: Tue, June 19, 2012 9:57:56 PM
> Subject: Re: [Nature Recordists] sanken cuw-180 recording
> =C2=A0
> > many manufactureres give the A-Weighting figure which
> > is rubbish. Sorry to be blunt, but A-weighting is for medium to loud
> > sounds and even then is not accurate to what we hear.
> I don't know where you got that idea; A-weighting is an approximation of =
> ear's response to low-level sounds, and as such is very useful. It has be=
> common to use it for medium and high-level sounds, and that mis-use might=
> the use of the term "rubbish."
> -Dan

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