Peter,
The capsules are positioned adjacent to (touching) each other, one above th=
e other. The front of the capsules are exactly flush with the surface of th=
e wing (main boundary surface) and next to (touching) the other boundary su=
rface formed by the nose piece.
Viewed from the front it would look a bit like this :| |:
I'm sorry I didn't photograph it as I made it, all this detail is now cover=
ed over with a permanent windscreen stapled onto the wood.
They are not glued in, I drilled a hole that was a snug fit for the rubber =
housing and eased them into position.
Each pair were soldered together, black lead to black lead, red to red. The=
se were then soldered to a stereo lead, a pair to each channel.
Like this :
Left ch. Capsule 1 Red -----
> soldered together then solde=
red to Red on stereo lead
Left ch. Capsule 2 Red -----
=
> this is the lef=
t channel
Left ch. Capsule 1 Black----
> soldered together then solde=
red to Black on stereo lead
Left ch. Capsule 2 Black----
=
=
> stereo jack plug to recorder.
Right ch. Capsule 1 Red -----
> soldered together then solde=
red to Red on stereo lead
Right ch. Capsule 2 Red -----
=
> this is the ri=
ght channel
Right ch. Capsule 1 Black ----
> soldered together then sold=
ered to Black on stereo lead
Right ch. Capsule 2 Black ----
I hope this helps,
Thanks, Ross
To:
From:
Date: Tue, 14 Feb 2012 01:20:09 +1100
Subject: Re: [Nature Recordists] Re: High tide at the Pebble Ridge, Westwar=
d Ho! Devon.
Ross, that design is for two larger mics, but you're using four capsu=
les. Can you please explain where you placed them on the wings, and how the=
y're wired up?
Have you glued the capsules in, or are they removable?
Peter Shute
--------------------------
Sent using BlackBerry
From:
To:
Sent: Mon Feb 13 22:55:33 2012
Subject: [Nature Recordists] Re: High tide at the Pebble Ridge, Westward Ho=
! Devon.
I was asked off-list for some more info on the recording, it may be of inte=
rest to the group so I have copied my reply below.
Ross
Of course, ask away...
The plans I followed are these from Rob D. He has designed two versions, th=
is link is to the smaller one, the one I made.
https://pantherfile.uwm.edu/type/www/audio-reports/BoundaryMicExperiments/i=
mages/PBB2N-Plans_SASS-LikeDimensionsSept2010.gif
If you look around on the site you will find a huge amount of information v=
ery generously supplied by Rob and other members of this group.
The em172 capsules were bought from the Frogloggers site, 10x caps for abou=
t =C2=A380, excellent service.
I have added a permanent wind screen around mine, (ie stetched lycra tights=
from my local pound shop) with a handful of duck down between the mics and=
screen.
Without this I found the mics far too sensitive to air movement to be useab=
le outdoors.
I also used a preamp BMA2
http://www.micbooster.com/products/felbattpreamp.html
This is not actual needed to run the capsules, they work on the low pip tha=
t the Sony M10 provides but I decided to give it a try.
The preamp supplies a higher voltage to the 4x capsules I hoped the mic's p=
erformance might improve if they were being supplied something closer to th=
eir rated operating voltage.
My impression is that using the pre-amp gives a fuller sound, ie more lower=
frequencies but I have not done a proper test.
To make my recording I waited for a combination of things ie. high spring t=
ide, a large swell, very little wind and a day off work to get there.
I had the mic array on a 2-3.0m boom which I was holding about 1.0-1.5m abo=
ve the surface.
I experimented with this position to try and balance the sound of the swash=
with the sound of the surf, otherwise the roar from the surf dominated the=
overall sound.
I was using the boom to get the mics far enough out so that the waves washe=
d right past me and the mics before receding, this effect is clearly heard =
as the wave passes from right to left.
The mics were positioned so that right =3D towards the sea, left =3Dtowards=
the land, this is probably different to the way you had yours.
I found that keeping the mic quite close to the surface and not using a lo-=
cut filter gave the best result.
Hope this helps,
Thanks, Ross
=20=20=20=09=09=20=09=20=20=20=09=09
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