At 6:15 PM +0200 9/11/05, Gianni Pavan wrote:
>Hi all,
> I just received a MOTU Traveller demo unit (a lot of thanks are due
>to BACKLINE, the italian MOTU distributor!). Before to install it on
>a katamaran for wideband recording ceataceans with our towed array of
>hydrophones I did a short test.
>
>It is a quite thin and lightweight, it stays just below the laptop
>even if it is a bit larger...
>It can be dc powered 10-24V (12W) or bus powered by the FireWire
>interface (it depends on your laptop's interface...)
Rather than use the laptop 's batteries through the FireWire
connector, I'd consider using a small sealed lead acid battery and
run power to both the laptop and the Motu separately.
>
>here the main features:
>4 mic inputs and 4 line inputs
>level controls in 1 dB step with numerical display
>levels are controllable either with the knobs&display or with the
>MOTU software
>up to 53 dB gain on mic inputs,
This is good news compared to 40dB gain. 53dB might be enough for
your application depending on whether you are interested in recording
ambience or individual sounds and the available sound levels. For
ambience, I find that 3% saturation of the peaks for the quietest
passages gives me enough data to work with. 6% is much better, but
<1% often disappoints. Since the NT1-A's have 25mV/Pa sensitivity,
they'll produce about as much saturation as most mics. You can run a
test in your quietest location and measure the peaks to see if they
are great than 3% saturation with the MotU pre at full gain. Best way
I know to check a units pre noise is to use two matched mics and
compare Mic-> Motu mic pre vs. Mic->external pre->Motu line input at
matched gains. Rob D.
--
Rob Danielson
Film Department
University of Wisconsin-Milwaukee
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