Hi Max,
I have also tested this unit and can confirm that it has a very flat frequency
response up to 90 kHz. The frequency response of such units is mainly
determined by the A/D converter chips in them. The E-MU Tracker employs the
AK5385A chip, which is one of the best A/D chips that are currently available.
http://www.emu.com/products/product.asp?product=17511&nav=technicalSpecifications
The frequency respones of the A/D chip at 192 kHz is described at page 10 of
its data sheet:
http://www.asahi-kasei.co.jp/akm/en/product/ak5385b/ak5385b_f00e.pdf
The relevant number here is the passband attenuation of only -0.06dB at 89 kHz.
This means that its frequency response at the 192 kHz sample rate is better
than that of the SoundDevices 7xx recorders for instance. The E-MU Tracker Pre
preamplifier noise level of -127dBu (unweighted) is also excellent.
So, combining the E-MU Tracker Pre with one of the cheap Netbook computers (and
a suited recording software) would indeed create a cost-efficient and still
high-quality recording system for stationary use in the field.
However, there is one detail that is a bit annoying. The firmware of the
E-MU-Tracker Pre does not keep the 192 kHz sample rate setting after switching
off the unit. So, you need to manually set the 192 kHz sample rate option on
its (software) Control Panel each time after booting the computer.
Regards,
Raimund
http://www.avisoft.com
--- In "Max Catterwell" <>
wrote:
>
> Hi Gianni,
> I have just been looking at this piece of equipment, and have more or less
> decided to buy. Did you get the graphs you mentioned done yet please? I'd be
> very interested to see them.
> All the best
> Max
>
>
> --- In Gianni Pavan <gpavan@> wrote:
> >
> > Hi all,
> > I would share some tech information about audio interfaces.
> >
> > the E-MU Tracker Pre is a USB powered audio interface with 192kHz
> > sampling. It costs less than 150$ and offers pretty good performances.
> > The frequency range is flat up to 90 kHz and the anti-aliasing
> > filtering is good. I tested it up to 200 kHz at full level and it
> > produces aliased components for input signals in the range 96 to 105
> > kHz; resulting aliases lie in the range 96 to 87 kHz. Graphs will be
> > shown soon on our website.
> > This interface has only analog I/O. At max gain the mic inputs accept
> > levels up to 18mVpp (measured between pins 2 and 3 of the XLR input).
> > By comparison, the Edirol UA 25 EX has greater gain: at full gain
> > (knobs fully turned clockwise) it overloads with input level greater
> > than 10mV.
> >
> > Gianni
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