David,
Thank you so much for taking the time to do such a detailed and helpful ana=
lysis. At the stage I am, it is extremely helpful just to see the steps you=
have taken to analyze what is going on. I will have a go at some targeted =
filtering using the guidance you offered.
> ...it sounds quieter in Surrey than down here in rural North Devon.
I can assure you that it isn't often quiet even in the more rural parts of =
Surrey. You are definitely better off in North Devon! We could also use so=
me of the rain in the (very nice) recording you posted. We are getting the =
wind today but only brief light showers and it is *very* dry.
> I like environmental sounds with the wildlife, and get the
> neighbour's sheep and cattle, but preferably not cars or planes
> which are boring.
Indeed. The animals add to the sense of place, but that can't be said for c=
ars and airplanes and low mechanical drones.
> I like the stereo placement - what mics are you using?
The microphone is simply the Audio-Technica BP4025 stereo mic. I was driven=
by wanting something very compact and quick-to-set-up for travel, and ther=
e don't seem to be many options in integrated, compact, low-noise, high-sen=
sitivity stereo microphones. The microphone was mounted on a tripod in a Ry=
cote suspension, with a Rycote mini-windjammer over the standard foam winds=
creen. It is cabled directly back to the recorder, which is a Marantz PMD66=
1 with the "SuperMod" done by Oade Brothers in the USA.
Thank you again for the help and taking the time to work with the recording=
.
Kin
--- In "Avocet" <> wrote:
>
> Kin,
>
> An excellent recording and it sounds quieter in Surrey than down here
> in rural North Devon. I like the stereo placement - what mics are you
> using? There is also very little "phasey" background effect which some
> systems produce. I reckon I can hear 9 sonels - discrete sound "pixel"
> directions and a good score.
>
> > Small sections of background drone are audible in a couple places
> > (most noticeably around the 5:40 mark -- I can't even tell for sure
> > if it is a distant car or a home furnace firing up or what exactly).
>
> I contructed an Audacity filter with a brutal cut above 150Hz. The
> power spectum shows a broad peak at about 70Hz which is resonant and
> comes and goes. I think the sound originally comes from distant
> traffic and/or distant aircraft rather than wind, but carried by the
> wind, but it may be all three. There's something resonating this with
> a dimension around 2.5 metres or an echo at about 5 metres path
> difference, or it could be something in the mic rig. I wouldn't rate
> this as a serious problem and it could easily be trimmed out by a
> bespoke filter. I's well clear of the pigeons which dominate the
> spectrogram. See the power spectrum taken from a quiet bit around
> 04:30 on
> www.stowford.org/images/spectrum110525.gif
> which has resonant peaks at around 70Hz and 100Hz. There rest are
> birds.
>
> I have a grain mill over a mile away which sometimes puts out a whine
> which comes and goes in the wind. I got church bells a couple of
> evenings ago behind the birds. I like environmental sounds with the
> wildlife, and get the neighbour's sheep and cattle, but preferably not
> cars or planes which are boring. The whine is a single frequency and
> easily taken out by a notch filter, again using the Audacity custom
> Equalisation feature.
>
> I recorded this in wind and rain this morning:
> http://soundcloud.com/stowfordnature/wind-rain-and-thrush-in-pig
> I wasn't in the wind and rain but the mics were, in a tent.
>
> Sometimes it's so quiet here I hear mic hiss even on my Sennheisers,
> and I reduce that with the noise reduction on Audacity which is
> selective, You show it what you want taken out and it reduces just
> that by a number of dBs. Noise reduction tends to destroy the ambience
> and certainly reduces reverberation which is so nice on your
> recording.
>
> My general rule is to leave backgrounds in, but to tailor that to what
> the ear hears, like wind noise which is worse on a mic, but your ears
> tend to ignore it.
>
> That noise around 5:40 is a puzzle. It could be a woodpecker pecking
> wood rather than drumming or a close nuthatch but there's too much
> echo for that. It could be a creak of course and a lister posted a
> recording of a creaky tree a few weeks back.
>
> David
>
> David Brinicombe
> North Devon, UK
> Cogito cogito ergo cogito sum - Ambrose Bierce
>
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