So you can hear it? That's a pity.=0D
=0D
If the even spacing discounts harmonics, perhaps there was some nearby equi=
pment that emits EMF at those frequencies. As I mentioned, it's an old salt=
works. They keep the water moving through for the birds, so there are pumps=
running.=0D
=0D
I also didn't mention that I simply placed the array on the ground. Perhaps=
the whole area is live, just waiting for recordists with badly shielded eq=
uipment.=0D
=0D
Peter Shute=0D
=0D
=0D
--------------------------=0D
Sent using BlackBerry=0D
=0D
________________________________=0D
From: =0D
To: =0D
Sent: Mon Mar 12 00:36:47 2012=0D
Subject: [Nature Recordists] Re: Initial SASS test shows bands of harmonics=
=0D
=0D
=0D
=0D
Oh yes, there it is. I wasn't zoomed in enough. I couldn't notice the sound=
originally but listening to the right channel again there is a slight 'fiz=
z'.=0D
=0D
The fact that the frequencies are spaced out by the same amount up the spec=
trum rather than being multiples is interesting.=0D
=0D
--- In <naturerecordists%40yahoogrou=
ps.com>, vickipowys <> wrote:=0D
>=0D
> The harmonics definitely show up using Izotope RX, just in the right=0D
> channel. I can't really hear any difference between the channels. I=0D
> don't know what is causing the harmonics but I should think it must=0D
> be either a faulty capsule or a poor connection. Perhaps touching=0D
> the capsules with the towel caused an earthing issue?=0D
>=0D
> Vicki=0D
>=0D
>=0D
>=0D
>=0D
> On 11/03/2012, at 9:50 PM, doctorobotnik wrote:=0D
>=0D
> > It would probably help if I included the link :)=0D
> >=0D
> > http://i.imgur.com/so7CG.jpg=0D
> >=0D
> > --- In <naturerecordists%40yahoo=
groups.com>, "doctorobotnik"=0D
> > <cookcommaben@> wrote:=0D
> >>=0D
> >> Hi Peter,=0D
> >>=0D
> >> This is how your test file looks in Audition's spectral view. I=0D
> >> don't see the harmonics you noted in the right channel. Perhaps=0D
> >> it's a quirk in Audacity. Do you have access to another spectrum=0D
> >> renderer to try the file on?=0D
> >>=0D
> >> Ben=0D
> >>=0D
> >> --- In <naturerecordists%40yaho=
ogroups.com>, Peter Shute <pshute@> wrote:=0D
> >>>=0D
> >>> Yesterday morning I made a 20 minute recording at the local=0D
> >>> wetlands with my new SASS array (4 x EM172's in a Rob Danielson=0D
> >>> style wooden structure, half finished - no nose baffle or=0D
> >>> internal baffling). I also made a recording using the Sony PCM=0D
> >>> M10's internal mics for comparison.=0D
> >>>=0D
> >>> When I loaded into Audacity and displayed the spectrogram, I see=0D
> >>> lots of bands on the right channel, about 400Hz apart, to 20kHz=0D
> >>> and beyond. I can't see any sign of them in the left channel, and=0D
> >>> I can't believe this thing has such good separation that it could=0D
> >>> be environmental. I can't hear anything odd, but with my hearing,=0D
> >>> that doesn't mean much.=0D
> >>>=0D
> >>> I also see no sign of it in the recording using the internal mics.=0D
> >>>=0D
> >>> So it must be generated in the mic circuitry? I just made another=0D
> >>> test recording with it on the table here beside me, and I see no=0D
> >>> sign of the bands on that recording either.=0D
> >>>=0D
> >>> So maybe it picked up some interference with it's unshielded=0D
> >>> wiring? Maybe, but would that look like this? And I was at least=0D
> >>> a kilometre from the nearest powerlines. The site is an old=0D
> >>> saltworks, so there may have been some pumps running a bit closer=0D
> >>> than that. The lead to the M10 is only metre long, and shielded,=0D
> >>> but there are a few inches of unshielded wiring in the array.=0D
> >>>=0D
> >>> More intriguingly, the first 20 seconds of the recording don't=0D
> >>> show the bands. This includes the sounds of me wrapping the array=0D
> >>> in a towel for wind protection. The last part, where I unwrap it=0D
> >>> again, also doesn't show the bands. That I don't understand at=0D
> >>> all. Unless perhaps my close presence somehow damped some=0D
> >>> interference?=0D
> >>>=0D
> >>> I've uploaded one minute of it in wav format if anyone wants to=0D
> >>> have a look at it: http://soundcloud.com/petershute/sass-test-=0D
> >>> harmonics. The first 20 seconds is very noisy and clipped, but=0D
> >>> I've had to include it to show the band free section.=0D
> >>>=0D
> >>> Peter Shute=0D
> >>>=0D
> >>=0D
> >=0D
> >=0D
>=0D
=0D
=0D
=0D
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