Jim Morgan wrote:
>>Did you get good enough figures to know what sort of dB drop the low
>>frequency filter is giving you at each of those bottom frequencies? I
>>believe you said it looked exponential.
>
>
> 50 and 60 Hz were about 12 db lower than the 80 Hz and the 80 to 200 was
> only about 1-2 db. Not really exponential, that was a poor term for me to
> use. This 12 db difference is quite a bit.
Sounds good. I'd worried at times it might be up above 200. I've got
frogs not much above that.
Kind of agrees with my experience.
>>I record nearly always with this filter on, because it's supposed to go
>>into effect at frequencies lower than any of the frogs I'm interested
>>in. And it does get rid of a lot of low frequency noise.
>
>
> I usually record with the filter on, if I don't wind and traffic noise ar=
e
> terrible.
Yep, and those that don't usually have to do the same filtering later.
If you ever get out trying to record thunder or such like, try turning
it off. The main energy of thunder is very low frequency.
Walt
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