Thanks for sharing the recording, David. I enjoyed listening very much
and I sincerely appreciate your positive comments about the hydrophone.
It does definitely sound like environmental noise in the background. The
crackly kind of sound usually comes from crustaceans and various reef
creatures. Surface noise is often a little more homogeneous--except for
the obvious stuff hitting the boat and so on. It is difficult in most
circumstances to get a very targeted recording in the absence of noise
in open water. But I think that all of that other stuff kind of adds to
the intrigue of the recording. I'd enjoy hearing a sample of your raw files.
There is a nice low-background-noise recording of humpback whales made
from the Dominican Republic by Gene Flipse on our website. Compare that
to a recording that I made last year while sitting in a kayak just a few
meters over a reef in Hawaii. I also find it interesting to listen to
the dialects of these whales from different locations. The recording
from Tonga sounds much different than the one from the Dominican
Republic--as I suppose you would expect. All of these can be heard from
the recordings page at our website:
http://www.aqaud.com/home.php?cat=29. While there, I would encourage
anyone to listen to Diane Okonek's excellent, and fairly rare, recording
that captures several unique walrus vocalizations.
Vicki, Yes, the H2a can be used with either phantom power or PIP. The
H2a-XLR and the standard H2a (with 3.5mm output plug) are actually the
same hydrophone now. Without getting too much into detail here: The
hydrophone is very well-shielded by design and grounded directly to
Earth in typical use. It is almost never used in an environment where
common-mode noise is a problem, So I chose to to make even the XLR
version run single-ended. It saves precious battery power and actually
has substantially less self-noise than the old impedance-buffered
balanced unit that we used to make. And it costs less. So the buffer
circuit in the H2 is designed more for versatility than for maximum
dynamic range or lowest output impedance with a phantom-powered
application. In my opinion, The extra versatility is a good trade and
there is still plenty of headroom for the nature recordist. And we use a
very high quality cable, so there is no problem with noise or
high-frequency attenuation with longer cable lengths.
If anybody would like more information, feel free to contact me directly.
Kind regards, Robb
On 3/10/2010 7:56 PM, vickipowys wrote:
>
> Wow! Amazing sounds David, and how adventurous to record from a sea-
> going kayak 2 miles from shore.
>
> In looking at the H2a hydrophones online I see that they make an
> adapter lead to 'use H2a hydrophones with plug-in-powered 3.5
> microphone jacks'. Does this mean the hydrophones could also be
> powered by PIP?
>
> Good luck for your future expeditions.
>
> Vicki Powys
>
> On 11/03/2010, at 9:57 AM, Kawika wrote:
>
> > Aloha Nature recordists, I pick up this thread from a few weeks
> > ago, having finally gotten out in a two-man sea kayak as I had
> > planned. We headed out South from Kaua'i and I dropped the 'phones
> > in about 300 feet of water about 2 miles out. Here is a condensed
> > and stitched together sample of my result--
> >
> > http://soundshawaiian.com/mp3/Hump%20more%20condensed%20Mixdown.mp3
> <http://soundshawaiian.com/mp3/Hump%20more%20condensed%20Mixdown.mp3>
> > or http://tinyurl.com/ykrqr9l <http://tinyurl.com/ykrqr9l>
> >
> > A very exciting time it was. I got about 45 min of this
> > conversation, not sure how far away the animals were, though we saw
> > adults within 200 meters.
> >
> > You can hear other whales more distant.
> >
> > Gear: Sony D50, ART Phantom II power supply, Aquarian H2a XLR
> > Hydrophones with 10 m cables from Rob Nichols. I didn't dare take
> > my SD 702 for fear of water damage.
> > Precautions: I kept the gear enclosed in a zip-loc inside a
> > waterproof dry-bag until conditions felt right. Then worked the
> > controls inside the dry bag. All worked well until the wind picked
> > up and I had to close up again, especially working back upwind as
> > the wind turned off-shore. I'm going out again, this time to drift
> > down-wind a few miles.
> > Post editing included 20db lowcut (recording was done without low
> > cut), 10 db cut above 2500hz, and several passes to reduce hiss.
> >
> > I like these new XLR hydrophones very much. I may need longer
> > cables to get deeper, as I think a lot of the hiss is from surface
> > noise, and maybe some distant snapping shrimp. The mics are quieter
> > in self-noise than this recording indicates.
> > Next time I'll also spread the phones more by suspending from bow
> > and stern, about 16 feet, whereas this time the spread was only 6
> > feet.
> >
> > I see a lot of hydrophone recording in my future, adding another
> > dimension to my Hawai`i soundscape collecting. Really fun!
> >
> > Aloha,
> > David
> >
> >
> >
>
>
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