From: Lang Elliott <>
>
>
> Going the analog route, unfortunately, means playing each file in real time.
> I really can't afford to do that. ProTools will just have to do for now.
>
> I wonder if enough folks in this group would like to have a copy of my 48Khz
> test file, which is an insect singing at around 12kHz. I think it is really
> demanding of any sample rate converter going to 44.1.
>
> Let me know if there's some interest and I'll post a wave file on my web
> site.
I've put up what I got off a copy of Lang's file:
Peak 4.03:
m("44khz_peak.aif","//madranis.home.mindspring.com/insect");">http:
Spark XL 2.81:
m("44khz_spark.aif","//madranis.home.mindspring.com/insect");">http:
Soundhack (osX version 0.892):
m("44khz_shak.aif","//madranis.home.mindspring.com/insect");">http:
The original Lang sent me:
m("48khz.aif","//madranis.home.mindspring.com/insect");">http:
I should note I also found a slight DC offset in the original, and
removed that before conversion. DC offset introduces it's own errors and
I routinely remove that.
Also, my system only outputs at 44k, so even listening to the original
it was already resampled. Spark and Peak played the original the same.
Sonograms showed in addition to the high frequency call centered on
about 12khz a band at about 5khz (the raspy sound) and a bunch of low
level sound below 170hz. The sonogram of the peak conversion does show
some very low level sound below the 5khz band.
Spark has batch capabilities, soundhack does not. I used best settings
in each, Spark was doing the math in 32bit floating point, not sure on
the others. Each has variations in settings available, and those do
change the outcome.
I have such lousy hearing at these high frequencies I was having to
really boost volume. To me Peak and the original sound about the same,
but that could be my hearing. Spark is different. I also did Soundhack
as well, somewhere between peak and spark. I had my son listen to them
all, he can listen to the high frequency at normal listening settings.
He said there was little difference to him.
Walt
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