naturerecordists
[Top] [All Lists]

Re: sound edit pops

Subject: Re: sound edit pops
From: "Dan Dugan" dandugan_1999
Date: Tue Oct 4, 2011 9:45 am ((PDT))
>> My standard technique is to make all audio cuts crossfades. It's
>> easy in a DAW. 15 ms is usually enough, 30 ms will be smooth. Try
>> it.
> 
> Agree, and Audacity has a linear cross-fade function precisely for
> this. Zero crossing cuts will not remove a DC component across the
> join unless the preceding half wavelength is exactly matched and
> opposite to the following half wavelength.

It's not only the DC component, but point well taken, as lots of digital audio 
includes a DC component. That means when there is no sound, the "zero" level is 
slightly up or down from actual zero. "DC offset" is another term for this 
artifact of A-D converters.

Even if there is no offset, a sine wave that stops dead has a whole string of 
harmonics associated with that event. That is what perpetrators of the myth 
neglect.

I'm not sure what you mean by "linear cross-fade," but IMHO the best cross-fade 
for splicing is "equal-power," i.e. 3 dB down at the center point.

> This problem takes me all the way back to the origins of tape editing
> with editing blocks which had an angled cutting slot.

Exactly. A 45-degree splice on quarter-inch tape at 7.5 ips is 33 ms--perfect.

-Dan










"While a picture is worth a thousand words, a 
sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause.



------------------------------------------------------------------------
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/naturerecordists/

<*> Your email settings:
    Digest Email  | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/naturerecordists/join
    (Yahoo! ID required)

<*> To change settings via email:
     
    

<*> To unsubscribe from this group, send an email to:
    

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/
 
------------------------------------------------------------------------

<Prev in Thread] Current Thread [Next in Thread>
Admin

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the naturerecordists mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU