Perhaps the M10 is more prone to this kind of thing with PiP mics than the =
LS10, not necessarily because it emits more radiation but because it can't =
supply as much PiP power, and this makes the capsules more sensitive to it.=
=0D
=0D
I normally keep my M10 attached to the top of my ME66/K6's shock mount just=
a few cm above the mic in order to avoid cable hassles with spontaneous re=
cording, and I've never seen these bands before. Perhaps the cable is bette=
r quality (I'm sure it is), but the K6 is powering the mic, not PiP.=0D
=0D
I'll be interested to see what happens if I make a battery box for these EM=
172s, or even just disconnect one pair.=0D
=0D
Peter Shute=0D
=0D
=0D
--------------------------=0D
Sent using BlackBerry=0D
=0D
________________________________=0D
From: =0D
To: =0D
Sent: Mon Mar 12 18:15:29 2012=0D
Subject: Re: [Nature Recordists] Re: Initial SASS test shows bands of harmo=
nics=0D
=0D
=0D
=0D
=0D
That's interesting Greg. With my Olympus LS10, when I use it with a=0D
really long lead to my bedside table (recording at night) I find that=0D
I can get a very slight hum (in both channels) when my hand is on top=0D
of the recorder, waiting to press the record button. When I take my=0D
hand away, the hum stops. The hum was worse with a lightweight=0D
cable, but much improved with a heavier well-shielded cable.=0D
=0D
The hum doesn't happen with a 2 metre lead that runs to my SASS Lite=0D
(with 2 EM172 capsules per channel). In any case, I usually just=0D
hang the recorder on the tripod and walk away, so as not to pick up=0D
breathing, shuffling feet, etc. My default setting is Low 10 which=0D
rarely clips.=0D
=0D
cheers,=0D
=0D
Vicki=0D
=0D
On 12/03/2012, at 11:49 AM, Gregory O'Drobinak wrote:=0D
=0D
> Well, after all of this discussion and Peter's observation about=0D
> the noise=0D
> essentially going away when the M10 is 1.5 m away, it reminded me=0D
> of my own bad=0D
> ex[erience at Seney last year.=0D
>=0D
> I set up my M10 in a waterproof case for an overnight drop and left=0D
> it. I was=0D
> pressed for time (and by hoards of mosquitos!), so I didn't take=0D
> the time to do=0D
> a headphone check before I left it. The next day I found that my=0D
> recording had=0D
> been ruined by a 'whiney' sound and I noticed that the shielded mic=0D
> cable had=0D
> been pulled across the front of the display. The noise. of course,=0D
> cvame form=0D
> the display refresh of the M10.=0D
>=0D
> ****The Sony M10's display is quite evil when it comes to=0D
> generating electrical=0D
> noise!!=0D
>=0D
> Do not have the M10 anywhere near your mics and keep your mic cable=0D
> extended=0D
> straight out & directly away form the mic jack.=0D
>=0D
>=0D
> Then don't attempt to hold the M10 with any part of your hand near=0D
> the display.=0D
> If you have to handle it at all while recording, hold it from=0D
> underneath with=0D
> your hand only touching the lower half of the metal case.=0D
>=0D
> I have run into this problem with many different mics, piezo=0D
> pickups, geophones,=0D
> etc., and it doesn't matter whether they are PIP'ed or not.=0D
>=0D
> The basic problem is that Sony completely botched the sheilding for=0D
> that display=0D
> (the backlight doesn't matter, it's the digital refresh) and when=0D
> you crank up=0D
> the gain for low-level signals, the display noise couples into the=0D
> input.=0D
>=0D
> Sorry I didn't think of this earlier, but now you know. Many other=0D
> recorders=0D
> have the same effect when touching the display, etc., but the Sony=0D
> M10 is=0D
> definitely the worst.=0D
>=0D
> Take care,=0D
>=0D
> Greg=0D
>=0D
>=0D
>=0D
>=0D
> ________________________________=0D
> From: Raimund <<raimundspecht%40google=
mail.com>>=0D
> To: <naturerecordists%40yahoogroup=
s.com>=0D
> Sent: Sun, March 11, 2012 7:32:30 PM=0D
> Subject: [Nature Recordists] Re: Initial SASS test shows bands of=0D
> harmonics=0D
>=0D
>=0D
> Peter, you wrote:=0D
>=0D
>> The clipped noise is from me handling the array as I wrap the=0D
>> towel over it.=0D
>=0D
> I just listened to your recording again. I can indeed hear the=0D
> (acoustic) noise=0D
> caused by the towel. But there is also another clipped noise at 6.4=0D
> and 6.9 sec=0D
> that has a different quality, which is alslo visible on the waveform.=0D
>=0D
>=0D
> I guess that this crackling noise is caused by poor electrical=0D
> contact between=0D
> the TRS plug and the mic input socket, which is a common problem=0D
> with PIP=0D
> microphones.=0D
>=0D
>=0D
> As far as I know, it is caused by the DC current that flows through=0D
> the=0D
> connectors. Such a poor electrical contact can then also increase=0D
> the overall=0D
> source impedance and so reduce the immunity against electromagnetic=0D
> interferences. That would be at least a consitent theory for the=0D
> sudden start of=0D
> the interferences at that point in time.=0D
>=0D
> Regards,=0D
> Raimund=0D
>=0D
>=0D
=0D
=0D
=0D
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