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Subject: AW: Editing files recorded on AJBR20
From: perterm (perterm_at_vce.de)
Date: 2004-02-24


> Von: DaveP
>
> Question: do you use an external mic for recording? Anybody know if the
> Archos mic would improve recordings like band rehearsals and gigs? Any
> other tips on how to get good quality recordings?

1.) Internal mic.
An external mic is mandatory for recording with the jukebox. The internal
thing is nothing but a toy solution.

2.) External mic -> line in
The analog circuit of the jbr is crap. The line in records quite a lot of
noise that is induced by all kinds of electronic. Especially changes on the
lcd are recorded very 'well'.

2a) With an appropriate mic preamp you can reduce this problem so that it is
bearable. Just make sure that you have the gain of the jbr reduced to
minimum and that the mic preamp does the amplification. That improves the
s/n ration very much. I don't own the archos mic/preamp thingie so I can't
tell anything about it. My homebrew mic preamp (based on the ssm2217) is in
charge to do the amplification for me.

2c) The analog input seems to have a built in limiter. You can record quite
'hot' signals without clipping.

2d) That being said: Don't rely on the peak meter to show peaks. It doesn't.
Even when you put it in "high performance mode". When you see it exceed
the -6 db mark regularily you can be sure that your recording contains
clips.

2b) Mind that the jbr records with a heavy shelf filter that reduces all
frequencies above 15 kHz. Don't expect very crisp sounding recordings via
line in.

3) digital in
In the past I used to record with my dat recorder as a ad converter and
recorded via the digital in of the jbr. That produced the best results and I
recommend recording digital whenever it is possible. There is no 15 kHz
shelf filter as with the analog in, no noise, nothing induced by any lcds or
hard drives, any meters an external ad converter has can't be worse than
that on the jbr. But this solution voids the portability - which was one of
the main reasons why I bought the jbr in first place. This also is the
reason why I rarely record with external ad conversion any more.

3a) Serious solutious for high quality recordings are expensive as you need
an external mic preamp with an ad converter. Especially when you want to
keep it portable there seem to be hardly any devices on the market. Those
that I could find are exorbitantly expensive - thus I haven't bought any
(yet). The only two devides I found which looked interesting to me are at
http://www.core-sound.com/inbox.html or
http://www.core-sound.com/Mic2496.html . If you are willing to make a few
drawbacks as far as the portability is concerned there are a few other
devices too. Some of them can be found at
http://www.oade.com/digital_recorders/Digital_Converters/index.html . If
anybody knows any other device (or a do-it-your-self-solution) for a
portable, battery powered mic preamp with spdif out, please let me know!

Phil

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