PS: the one at 23.2s does seem a bit of an outlier.
The one at 30.6s is followed by an echo, I think, at 32.9s.
Likewise 35.2s is echoed at 37.6s.
I wonder if there's a high ridge about a km away that is reflecting it.
Perhaps the source is in the opposite direction from that?
On Mon, Nov 5, 2012 at 5:16 PM, Keith Smith <> wrote:
> Hi Peter,
> Here's a screenshot from Raven Pro (I took the $100 deal) -thanks for the
> fodder!
>
> http://www.samplesmith.com/NatRec/MurraySunset_Raven.jpg
>
> With the reverberations and repetitions, I'm thinking its source is much
> farther away. Maybe a military gunnery range within 30-40 miles?
> Keith
>
>
>
>
> On Mon, Nov 5, 2012 at 3:34 PM, Chris Harrison <>wrote=
:
>
>> **
>>
>>
>> Possibly an Emu? They make a deep thumping like that.
>>
>> Were there emus around?
>>
>> Chris Harrison
>>
>>
>> -----Original Message-----
>> From:
>> On Behalf Of Peter Shute
>> Sent: Monday, November 05, 2012 1:59 PM
>> To:
>> Subject: [Nature Recordists] RE: Background thumps in recording
>>
>> Well, that was smart. I forgot to include the link to a sample of the
>> recording:
>> http://soundcloud.com/petershute/dawn-chorus-pheenys-track
>>
>> I've put comments where all the thumps are in that one minute sample.
>>
>> Peter Shute
>>
>> ________________________________
>> From: =
]
>> On
>> Behalf Of Peter Shute
>> Sent: Tuesday, 6 November 2012 5:52 AM
>> To:
>> Subject: [Nature Recordists] Background thumps in recording
>>
>> I recentlly made some recordings in Murray Sunset National Park, in nort=
h
>> west Victoria, Australia. It was, I thought, a very quiet place in the
>> mornings before the wind started, apart from the birds.
>>
>> But in one recording, there is a thumping noise at random intervals, rig=
ht
>> through the two hour recording, which starts just before sunrise. Could =
I
>> please have some opinions on what these noises might be?
>>
>> At first I thought they were a car door being slammed - we were camped
>> about
>> 300m away, just over the hill - but there are far too many of them.
>> Gunshots? Not allowed in the park, and the nearest farms are over 10km
>> away,
>> although it's still possible, as there are feral goats in the park.
>>
>> I'd also like to know if there's a good way of finding all of these in t=
he
>> recording without having to listen to it. I can only hear them if I use
>> headphones, and if there's no background noise in the room, so it took m=
e
>> a
>> while to find as many as I have.
>>
>> After I'd found a few just by listening, I used EQ to reduce everything
>> above 400Hz and increase everything below 200Hz. This makes them way mor=
e
>> obvious to the ear, and I can spot most on the waveform, but it's not ve=
ry
>> pleasant to listen to. It also makes the sound of wingbeats sound simila=
r,
>> so I made a few mistakes.
>>
>> Could there be an automated way of finding them all, or making them
>> reliably
>> more obvious on the waveform? I use Audacity.
>>
>> Peter Shute
>>
>>
>> ------------------------------------
>>
>> "While a picture is worth a thousand words, a sound is worth a thousand
>> pictures." R. Murray Schafer via Bernie Krause.
>>
>> Yahoo! Groups Links
>>
>>
>>
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