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Re: Clock test between HD-P2, 671 and SD722

Subject: Re: Clock test between HD-P2, 671 and SD722
From: "Raimund Specht" animalsounds
Date: Thu Jan 4, 2007 1:56 pm ((PST))
I did that test one year ago. So, I'm not sure whether I remember all
the details correctly.

> >http://www.avisoft.com/sratch/HDP2_671_SD.wav
>
> Raimund--
>
> Great! I'll study them closer. I have a few, probably useless
> questions, but so I'll know:
>
> All recorders were at full gain, right?

Yes, I think so.

> At what level did you normalize the three tracks? I see ~ -35dB as-is.

I don't know. I just tried various multiplication factors until I got
a uniform intensity. Note that this procedure is note very accurate
because the short clock pulses are quite variable (actually it would
be better to use a constant sine signal as a reference tone).

> Was the bit depth and sample rate the same on all three orig recordings?

Yes, all were recorded at 44.1 kHz and 16 bit.

> Did you normalize the files in 24 bit state and then truncate the
> combined mix to 16 bits?

As far as I remember, I did this particular test in 16 bit. So, you
might argue that there occured some rounding effects that increased
the noise. However, I also did other test before at 24 bit resolution
that subjectivly provided similiar results.

> First listen thought: The 722's recording saturation seems "thin" to
> me. Might be the affects of being in a much more remote location than
> I am?  The hiss seems higher on all three than I would expect,..

My clock is obviously a bit quieter than yours. The distance between
the mic and the clock was about 0.5 m.

Regards,
Raimund







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