Hi Aaron,
Yes, I'm also a bit concerned about the harmonic sequence (fundamental
frequency of 4.8 kHz) in the 722's noise spectra. I repeated the 150
ohms termination test several times at different locations both at
work and at home (where I switched off the main fuse in order to
minimize electrical interferences). The magnitude of that noise varies
from time to time, but it is always there. So, I think that it must be
a flaw of my SD722.
There are similar (but softer) harmonic noise component in the HD-P2
spectra at 11.0 an 11.4 kHz, which seem to be a (very minor)
systematic flaw of the HD-P2 (I found it on two different units).
I guess that those harmonic noise components originate from the
internal DC/DC converters or other clocked electronic components
inside the recorders.
The louder high-pitched artifacts in the normalized recordings
probably have been picked up by the microphones.
Regards,
Raimund
--- In "Aaron Ximm" <>
wrote:
>
> Thanks Raimund, fantastic work!
>
> On the 722's noise spectrum chart, it appears there's a harmonic (?)
> sequence popping above the floor, do you attribute that to the 722
or do you
> think it's an artifact?
>
> On my crummy speakers here at work I believe I can hear a high-pitched
> artifact in the normalized 722 recording, but it could just be these
Yamaha
> desktop speakers or my noisy integrated sound card...
>
> best,
> aaron
>
> On 2/1/07, Raimund Specht <> wrote:
> >
> > As announced previously, I just completed another noise (and max gain)
> > comparison test on various microphone and recorder combinations.
> >
>
> --
>
> quietamerican.org
> oneminutevacation.org
>
> 83% happy
> 9% disgusted
> 6% fearful
> 2% angry
>
>
>
|