At 11:25 PM +0000 5/8/09, Dave A. wrote:
>Hi all--
>I have a Dumb Question- do you absolutely need to record sounds at
>'high' level...? Esp. if you're using a digital recorder?
>
>I know that the original reason for recording at high levels, ie w/
>analog equipment, was to raise the signal as much as possible above
>the noise floor, which usually was the tape transport/etc. But now,
>if we're recording digital, & whatever noise is generated by the
>pre's anyway, then what's the difference between recording w/ lots
>of gain in the field... vs. just adding gain later in 'post?
Hi Dave--
You are correct, under almost all conditions, there is no longer a
need to attain close to maximum saturation levels for the sake of
decreasing noise. Recordist can take advantage of the much improved
noise performance of digital recorders over analog tape and record
peaks at much lower levels without issue.
>Ie, are good pre's able to add significant gain w/o increasing
>relative noise, ie something which you couldn't do in 'post (eg. a
>'gain' increase made in post would increase both signal & noise
>equally).
>
>I've tested the difference on some live music &/or lectures I've
>been recording, & can't tell the difference... so does this make a
>bigger difference with very quiet original sounds?
These sound sources are on the order 20- 70dB louder than recording
ambience in "quiet" natural locations. As you have probably observed,
they require little "gain" on the part of the recorder's mic preamp
and the noise associated with the mic (self-noise) and the noise of
the recorder's mic preamp (input noise) are usually not audible. Same
is often true when isolating bird calls with a dish or directional
mic.
Its only when the recordist is interesting in capturing some of the
acoustic character of the space, or "ambience" and the sound levels
are low that the noise performance of the equipment will become
apparent.
Yes, the advantages of using very low noise equipment options under
these conditions will become very noticeable. Even with highest
performing gear, under the quietest conditions, the self-noise of the
mics will be evident .
Sound levels play a key role in noise performance and describing the
setting you are in and the sounds you are after is important when we
discuss techniques and gear. Very low noise gear is very important
for some nature recordists and much less important for others. Should
you have more questions about noise/sound level relations, searching
a string of terms like "very low noise" in the list archive of posts
(e.g. http://tinyurl.com/qrkezn) will provide a lot of information.
I hope this short discussion covers enough of the principles to make
that reading more productive. Feel free to post follow-up questions.
Did you get some wl-183 mics soldered-up? Rob D.
>
>TIA,
>dave
>
>
>
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