Hi Robb, I uploaded to files a brief mp3 comparison between raw and mangl.. er,
processed recordings, titled "Hump for nr" http://tinyurl.com/y9kja2m
If you would like a larger file I could send you a .wav by ftp, but can't
over-load the group files.
I listened to your "recording that I made last year while sitting in a kayak
just a few meters over a reef in Hawaii"--astounding! For me the question is
begged, Where are the snapping shrimp? if you were only a few meters over a
reef. Or were the Humps so loud that the shrimp receded into the background? My
reason for going out in the kayak of course is to escape the shrimp.
I have 10 meter cables with my H2a's, do you think I would benefit having
longer cables, to better avoid surface noise?
Aloha,
David
--- In Robb Nichols <> wrote:
>
> 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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