audio editing

7 replies [Last post]
stoo
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Joined: May 28 2001

I hope some one can explain this to me... Im learning how to use cool edit pro and I was wondering what these functions did.. Im also reading a book called pc audio editng, which has been a massive help but has left me un clear on these ....

Normalise am I right in thinking that this centres (if you tick the box) the dc offset and then sets the level so that the loudest sound doesn’t distort/clip.

Hard limiting what function dose this do?.. from what I have seen it makes every thing louder, so for radio production where/how would this be used?.. the only example I have come across is peaky sound where if you have some one that speeks quietly but pronoces certain words/syllables loud… what other ways is this used?.

And statistics why would I need to no the max/minsample value? And the peak amplitude? And the max, min, average, total rms power?

SIMAnt
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Joined: Jan 9 2002

>>Normalise am I right in thinking that this centres (if you tick the box) the dc offset and then sets the level so that the loudest sound doesn’t distort/clip.<<

Yes. Also, if theres a particularly out-of-place sound that you dont want (e.g. a pop) that creates a peak whereas the loudest point of music is quieter than this, then you can zoom in and cut out the peak and CEP will redraw the waveform so you don't create a click. Then normalising will bring the highest point of music to just underneath clipping level. If you're working with audio that you've exported and are planning to re-import into your editing program its best not to do this as speech can lose lip-sync...

stoo
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Joined: May 28 2001

thanks for that, Ill make note about the speech...
can you help me with any of the others?...

Alan Roberts at work
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Joined: May 6 1999

A lot of the features in any powerful software are there only because someone once asked for them. It was possible to do and increased the number of features in the list, So, why not? It leaves many choices that you'll never need or make, or possibly even understand, but that shouldn't stop you using what it does best for you. I use Coold Edit 2000, mainly for noise reduction and equalisation. The functions I don't understand are all those that I've not tried yet. Some may be useful later on, but for now, as long as it does what I need, I'm happy that it can do lots of things that I don't need provided that it does what I do need and does it well.

My 2 pen'orth

Mike Henson
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Joined: Oct 10 1999

I use Sound Forge and Samplitude Pro but the teminology/functions are the same.

Normalise is useful where you have several audio clips all at different levels. The programme scans the file and shifts the whole signal up or down proportionally to peak at the level you've set.

Limiting stops the signal from going over the threshold you've set either "hard" or "soft" refers to how violently the limiting cuts in. Limiting is usually used in conjunction with compression which comes in at the same time and creates a situation where (say) a voiceover which originally had peaks and troughs is all the same volume after processing.

Hope this helps

Mike Henson
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Joined: Oct 10 1999

Sorry, forgot.

I've never lost sync by exporting processing and then importing the spoken voice - maybe it's a bug with Cool Edit?

If you resample the .wav file or subject it to any pitch shifting then that will change it's duration which of course will cause sync to drift.

SIMAnt
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Joined: Jan 9 2002

Cutting out unwanted peaks as opposed to redrawing them (which may be used, for example, to remove clicks or pops on the soundtrack of an old video) will also change the length of the wave file and therefore make lip-sync drift.

Mike Henson
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Joined: Oct 10 1999

Firstly you zoom in and only remove the peak rather than ten minutes either side of it and secondly, if it's time critical you "mute" the peak rather than remove it.
Hope this clarifies the procedure.