Hello Klas, Doug, Walt, et al.,
JOHN (John V. Moore Nature Recordings) wrote:
>
>I hesitate to post this on the list server because
> some of the questions I have will be very basic to many, but the DELETE
> button is, thankfully, easy for all to use!.
>
The same goes for me. Only more so! I'm so technically ignorant that I
don't even understand what impedance is. On May 29, Klas wrote:
>
> No designs today have low input impedance. The input impedance of a recorder
> is always 2-10 kiloohms. I know SQN had a transformer input on some
> pre-amps, but that was long ago.
> This is the one and only principle for impedance matching: The input
> impedance must be much higher than the output impedance.
> All recorders / mic amplifiers today have an input impedance around 2 - 10
> kOhms.
>
When I started recording bird song (06:00 hrs Oz EST, June 21, 1968) I had
the good fortune to have been well advised on the recorder: I had a Uher.
(Recently overhauled, and apparently working well. How's that for a 30
year-old piece of technology!)
I was also advised that to get a good recording of a lyrebird one needs to
place a mic on a long lead, where the bird is going to sing, and for this,
one must use a LOW IMPEDANCE microphone. The Uher mic I got with the
recorder worked OK with 50 metres of cable, and so too did a couple of
Sennheisers I got later. I assumed they must be low impedance.
Of the shotgun Sennheiser (MKH-815), a friend said that what the Sennheiser
people don't tell you, is that you can put the power supply at the recorder
end of the long cable. I have soldered up a few connectors, but I thought
of the cost of the mic. and the depth of my ignorance of electronic matters,
and didn't try!
A couple of years ago I got a Tascam DAT recorder and have successfully used
a small Sennheiser ME 20 on the long cable with it. But I now have the
great good fortune to have a Telinga mic which is just so much better. I
feel sure that with the reflector it will be a definite improvement over a
shotgun mic for recording lyrebirds at a distance - if the poor
drought-stricken lyrebirds sing this year.
But can I use the Telinga mic. on a long cable? Is it of low impedance - if
indeed that is critical?
If so, is it a matter of getting a suitable cable and connectors and still
using the Tascam's phantom power? Or is it possible to get an external
power source for the Telinga? The latter, I would prefer: lyrebirds
sometimes sing for an hour or more, and battery life becomes critical. One
doesn't wish to have to change a battery in the middle of a performance:
Murphy's Law applying, that would be exactly when something unusual
happened.
I would use the Services of Music Lab, a local electronics firm, to make the
cable, and external power supply, if that is possible. Tascam/TEAC are
pretty big in the music industry, and I'm sure Music Lab would be familiar
with the Tascam recorder. But not the Telinga microphone. And in the music
industry they probably don't get much call for recording 50 metres away from
the microphone(s) and kilometres away from any power supply - 240 V mains AC
or even motor vehicle 12 volt DC.
It usually takes me a few days study of an individual lyrebird to get him
singing at my mic. And if I've gone to that much trouble, it would be great
to be able to take advantage of the outstanding Telinga quality.
Any advice would be most gratefully received.
TIA
Syd Curtis (Brisbane, Australia)
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