Justin & All,
It IS possible, on a Mac, to remove jet noise, not perfectly but
quite well. It depends though on what frequencies you wish to retain.
I sometimes make long recordings of lyrebirds for research purposes,
and it is inevitable that every now and then a jet will fly overhead,
fairly high up. With lyrebird song, long continuous sequences are
necessary for study, and it is good to be able to keep on recording,
knowing that you can later get rid of most of the jet noise.
Lyrebird song is in the frequency range of, say, 700 Hz - 5 kHz.
Most of the roar of a jet plane (if high overhead) is below, say, 500
Hz. So you make up a brick wall filter e.g. with TrackPlug 5 and
Peak, and on your recording you completely cut out everything BELOW
500 Hz.
This leaves you with an unnatural sounding recording, although the
lyrebird frequencies are still untouched. Next step is to take a
recording of relative silence from the same place, same time, copy
and paste if necessary to make it the required length. Then apply a
brick wall filter to this so that you cut out all frequencies ABOVE
500 Hz.
Now mix the two sequences together (easy with Peak), and adjust
levels. You have now restored the full range of frequencies, minus
the roar of the jet, for a natural sounding recording.
I tried doing this just now, and there was still some slight residual
jet noise, so again in TrackPlug 5 I made a notch filter at 500 Hz,
and this helped a lot. I will post a short lyrebird recording that
demonstrates 'before and after'.
Hope this helps! And thanks to Ed Slater who first suggested the
brick wall filter method, and to someone on this list who recommended
TrackPlug5 as a replacement for Waves Q10.
Vicki Powys
Australia
On 08/04/2009, at 11:48 PM, justinasia wrote:
> (snip)
>
> On a slightly different topic, if one did come into my recording,
> is there any hope of removing it while keeping the rest of the
> sound? (I mean, remove those frequencies, not just cut out that
> part in time). If so, what software would I use (Mac)?
>
> Justin
>
>
>
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