naturerecordists
[Top] [All Lists]

Re: A few newbie questions and my not-so-porable setup

Subject: Re: A few newbie questions and my not-so-porable setup
From: "Rich Peet" <>
Date: Wed, 20 Aug 2003 20:46:28 -0000
Just a few additions to Walts post.

You may find as we did at our open nature recordists campout, big 
problems in using a power inverter in the field. The negative post 
from a battery before a power inverter does not have the same ground 
voltage value as the negative voltage after the power inverter.  Also 
known as a floating ground.  This leads to big problems with noise 
while recording which increases as soil moisture increases. Only use 
the inverter to charge batteries not to record from.  We ended up 
having to hang a car battery suspended from a tree to mitigate the 
problem which never was eliminated completely. Consider motorcycle 
batteries for a cheap solution and there are a bunch of spendy 
solutions. Keeping things at DC means no AC hum problems.

On long cable lengths if a perm installation consider underground 
irragation pipe to run your cable in.  If a temp installation the 
best cable for all-season work is Canare star quad low profile 
cable.  You can still coil it and un-coil it in freezing conditions.

For recording 2 channel only at 44.1khz, 16bit an old pentium 
laptop "chunk-o-junk" is plenty good. If you use a better machine 
make sure you get your insurance upgraded to a scheduled all risk 
coverage for it. You need coverage than for flood, breakage, and 
mysterious disappearance.  I am one of those advocates of laptop 
recording because a laptop is still the cheapest entry into this 
field and it can double as your editing station.  This is because a 
computer is needed for editing sound anyway and both bases can be 
covered with one unit this way.  

I use Cool Edit 2000 in the field which was free after having 
upgraded to Pro after getting 2000.  I hope Adobe doesn't hurt 
Cooledit with time now that they bought the rights.  I also record 
with a small program called AudioMagic 2.2.  It is cheap, small and 
gives you VOX and a completely programable length pre-record buffer.

Many laptop soundcards while running off batteries are surprising as 
to what they can do.  Many are Mono mic in. But then you can add an 
external sound card or preamp with line level output if you want or 
need.

Rich Peet


--- In  Walter Knapp <> 
wrote:
> Richard wrote:
> > What is the performance of Minidisc recorders vs. a PC soundcard 
input? 
> > 
> 
> Minidisc recorders are not a monolithic thing, there are quite a 
few 
> models of both consumer and pro level. Most minidisc recorders will 
have 
> better inputs for mic recording than soundcards do.
> 
> > 
> > Do the MD recorders have "real" mic inputs, or are preamps 
required to
> > drive line inputs?
> > 
> 
> real mic inputs, real preamps.
> 
> > 
> > Many condenser mics require 48V phantom power. How is this 
handled?
> > 
> 
> The pro recorders like my Portadisc have XLR inputs and supply 
phantom 
> power if needed. For consumer "walkman" minidisc a separate power 
supply 
> is necessary. Usually supplied in conjunction with a higher quality 
mic 
> pre like the recently discontinued Sound Devices MP2.
> 
> > 
> > How many of you have taken notebooks into the field as recording
> > devices?
> > 
> 
> I have used notebooks in the field, but not as recording devices. I 
> strongly recommend a made for the purpose field recorder over using 
a 
> notebook.
> 
> > To go mobile, I would need a 12VDC-to-120VAC inverter since the 
Art Tube
> > MP's wall adapter supplies AC rather than DC. I would either have 
to lug
> > a 12V battery or stay near a vehicle.
> > 
> 
> This is only part of the problem of going mobile with a notebook. 
The 
> notebook is really designed to be portable from desk to desk 
indoors. 
> It's very risky for the notebook and very inconvenient.
> 
> > The notebook could run off its own batteries and charge off the
> > inverter.
> > 
> 
> If you go this route you would not actually have to cart the 
inverter, 
> particularly if you are going there in a car. Have enough batteries 
for 
> your portable periods, and use the inverter in the car to recharge.
> 
> > 
> > Since my home backs up to a bayou and wild area, I have gotten 
some good
> > results just placing the mic in my backyard. I may experiment with
> > longer cables to get it further out.
> > 
> 
> I you hunted up Lang's comments on the hazards of long cables you 
would 
> discover that there are distinct limits there. His problem was the 
> beaver would chomp through the cables.
> 
> While I'm sure you can get quite a bit of stuff from your yard, you 
will 
> find there's lots more if you are fully portable.
> 
> > 
> > Has anyone ever used a setup at all similar to mine?
> > 
> 
> There are some in the group who advocate and have used notebooks as 
> recorders. I use a HHb Portadisc minidisc field recorder.
> 
> > 
> > What are the preferred mics?
> > 
> 
> That's a endless subject and there are a large variety of good 
choices. 
> It contains within it how much you are willing to spend, what sound 
> quality satisfies you, what sites you wish to record and what 
sounds. As 
> well as more. There is really no one preferred mic, or even one 
> preferred type. Decide in some way the stuff above and then look at 
what 
> fits.
> 
> For high quality recordings the mic is the most important piece of 
> equipment, followed by the preamps and last the rest of the 
recorder. 
> Unfortunately very high quality mics are expensive. Most make some 
sort 
> of compromise and live with somewhat lower quality mics. Good 
recordings 
> can be made even with fairly low quality mics, but often with a lot 
more 
> effort.
> 
> The most common mic types in nature recording have traditionally 
been 
> parabolic microphones and shotgun microphones. These are used 
primarily 
> to record calls. Parabolic microphones provide extra gain due to 
the 
> reflector, and the same reflector provides considerable rejection 
of 
> sounds off axis. They provide the sharpest directionality. Shotgun 
mics 
> provide rejection of off axis sounds, though not as narrow as 
> parabolics. They provide no extra gain above that of a more normal 
mic, 
> so require more amplification than parabolics. I mostly use a 
Telinga 
> Pro V stereo parabolic for call recording. Others make different 
choices.
> 
> Recording of ambiance as opposed to individual calls is another way 
to 
> go. Here sharp directionality is usually not wanted. Stereo is a 
big 
> advantage. (Stereo is also a advantage in call recording). Natural 
> ambiance contains times when the sound level is very low. This will 
> reveal the self noise that all mics have, so very low self noise is 
a 
> requirement for a mic used for ambiance. This is a big cost factor, 
low 
> noise mics are more costly by a wide margin than more noisy ones. 
The 
> self noise of the rest of the recording chain has to be low too.
> 
> In addition to the Telinga, I currently routinely use:
> Three different M/S stereo setups, all using Sennheiser MKH mics:
>   A MKH-60/MKH-30 combo, the MKH-60 is a short shotgun mic.
>   A MKH-40/MKH-30 combo, the MKH-40 is a cardioid mic, the MKH-30 
is a 
> figure 8 mic for the side mic.
>   A combo of two MKH-80 multipattern mics.
> Two different modified SASS setups, again Sennheiser mics:
>   A SASS with MKH-20's
>   A SASS with MKH-110's
> I also have a pair of MKH-816 long shotgun mics that I've yet to 
get 
> kitted out with suspension and windscreens. And some other mics 
awaiting 
> setup.
> 
> The Sennheiser MKH series is their top mics. They are very 
expensive. I 
> saved a large amount of money finding them on Ebay. Though that 
used 
> lots of my time. The Sennheiser ME series mics will work well, they 
are 
> the next step down, though there is no figure 8 mic in that series 
to 
> make up M/S combo's. A few mics of other brands will work. Many 
mics 
> won't, either being too noisy, or too sensitive to environmental 
> conditions, especially moisture.
> 
> Walt
> 




________________________________________________________________________
________________________________________________________________________

<Prev in Thread] Current Thread [Next in Thread>
Admin

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the naturerecordists mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU