Thanks to all those who responded to my question. It has given me a
greater insight into mic. selection than I have been able to find
elsewhere to date. Never being a betting man, I can see in some ways it
is trying to pick a horse from the form guide, you may pick a good one
but it may depend on the conditions and how real it is ridden if you got
a winner or not. Many thanks
David
Rob Danielson wrote:
> At 12:26 PM -0500 2/17/05, Walter Knapp wrote:
> >From: Rob Danielson <>
> >
> > > Hi Klas--
> >>
> >> I agree that people need to understand that the self noise
> >>component is fixed.
> >
> >I'm not so sure I agree with such a statement without a lot of
> >qualification. The self noise does get amplified with the rest of the
> >signal. Therefore, as you change the gain on the pre, it's level changes
> >too.
> >
> >About what stays fixed is it's relationship to the sound you want. If
> >the self noise is 30 dB below the sound you want, and you amplify the
> >signal, it will still be 30 dB below the sound you want, but louder.
> >
> >What we are really wanting to do is keep the self noise below the
> >threshold of hearing, or failing that, at least below the threshold of
> >awareness. And that's for the final playback volume.
> >
> >Walt
> >
> >
>
> Sorry I'm not making myself clear. The relation I hoped to describe
> with the phrase "noise component" is that the self noise introduced
> by the mic is part of the total signal as a fixed percentage. The
> noise introduced by the mic pre, at its current setting, is also a
> fixed percentage.
>
> The Rode NT-4 mic has 6.5 dB(A) LESS self noise than the Shure 183
> but the NT-4 produces a recording with MORE noise when MD record gain
> is set at 23-- which is typical for outdoors. Taking the mic self
> noise spec alone can be misleading, especially if one is interested
> in recording ambience.
>
> I appreciate Walt's framing of mic self noise in relation to ambient
> sound levels because in some situations it is totally irrelevant. I
> can set levels for a cardinal at 15' or a snow blower down the block
> and play these recordings back without noise becoming a significant
> part of the experience.
>
> However, when recording ambience under quiet conditions- mammals
> walking through the woods at night, the hush of dusk, the murmurings
> of a city at 3am on frigid winter morning-- the noise introduced by
> mic/mic pre combination is a very audible component of the
> recordings. I'm interested in the details of these spatial events so
> when I play these recordings, I'm amplifying the original event 50dB
> or more. In contrast, a frog or bird call played over many recordists
> speakers might be amplified ~6dB louder during home playback.
> Mic/pre Noise plays a very different role in these contrasting
> playback situations. Rob D.
>
>
>
>
>
> "Microphones are not ears,
> Loudspeakers are not birds,
> A listening room is not nature."
> Klas Strandberg
>
>
> ------------------------------------------------------------------------
> *Yahoo! Groups Links*
>
> * To visit your group on the web, go to:
> http://groups.yahoo.com/group/naturerecordists/
>=20=20=20=20=20=20=20
> * To unsubscribe from this group, send an email to:
>
> <=3DUnsu=
bscribe>
>=20=20=20=20=20=20=20
> * Your use of Yahoo! Groups is subject to the Yahoo! Terms of
> Service <http://docs.yahoo.com/info/terms/>.
>
>
>------------------------------------------------------------------------
>
>No virus found in this incoming message.
>Checked by AVG Anti-Virus.
>Version: 7.0.300 / Virus Database: 266.1.0 - Release Date: 18/02/05
>=20
>
--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.300 / Virus Database: 266.1.0 - Release Date: 18/02/05
________________________________________________________________________
________________________________________________________________________
|