There is a function which will find the "zero crossing" (place where there is zero amplitude for the sound wave) in an audio file and automatically make it the border of your audio region, thereby avoiding pops and clicks when the audio region is played. But it seems that mine just doesn't work! When it is turned on, and I select a new border for the region, the border is not at a place of zero amplitude, and the region starts off with a pop. why might this be? thank you to anyone for your help

On Apr 11, 2007, at 7:38 PM, douglas roberts-wolfe wrote: > There is a function which will find the "zero crossing" (place > where there > is zero amplitude for the sound wave) in an audio file and > automatically > make it the border of your audio region, thereby avoiding pops and > clicks > when the audio region is played. But it seems that mine just > doesn't work! > When it is turned on, and I select a new border for the region, the > border > is not at a place of zero amplitude, and the region starts off with > a pop. > why might this be? thank you to anyone for your help I wonder if there is a DC offset happening. Try the "remove DC offset" before you edit the audio, and see if that get's rid of the pop. Just a hunch. George Leger III ________________________________________________________ http://www.myspace.com/georgelegeriii http://www.utopiaparkwaymusic.com Mac AND PC: The only way to fly 8-}

> Message posted by douglas roberts-wolfe <obleetorcron@...>: > There is a function which will find the "zero crossing" (place > where there is zero amplitude for the sound wave) in an audio > file and automatically make it the border of your audio region, > thereby avoiding pops and clicks when the audio region is played. > But it seems that mine just doesn't work! When it is turned on, > and I select a new border for the region, the border is not at a > place of zero amplitude, and the region starts off with a pop. > why might this be? thank you to anyone for your help > What window are you doing your editing in? The search for zero crossings command is found in the Arrange, Audio and Sample editor windows. I'm of the opinion the Arrange window has an issue with snapping to a tick (1/240th of a 16th in 4/4 time) rather than really going to a zero crossing. Doug

> Message posted by douglas roberts-wolfe <obleetorcron@gmail.com>: > > There is a function which will find the "zero crossing" (place where there > is zero amplitude for the sound wave) in an audio file and automatically > make it the border of your audio region, thereby avoiding pops and clicks > when the audio region is played. But it seems that mine just doesn't work! > When it is turned on, and I select a new border for the region, the border > is not at a place of zero amplitude, and the region starts off with a pop. > why might this be? thank you to anyone for your help There could be 3 reasons for this: First of all, since the arrange window thinks in tics and not in time, the search zero crossing most likely only works on the audio editor (where you can resize and move regions in the time domain, totally independant of tempo and measures). Second, zero crossings only prevent pops if they come in pairs. If you start a region with a zero crossing, it will still pop if the previous region didn't end in one. Finally, if two regions overlap, searching zero crossings doesn't help at all because the first one stops playing where the second one starts and there is no way to be sure they _both_ cross zero there. So a crossfade is then the only way to guarantee pop-free playback. Maurits.

--- In logic-users@yahoogroups.com, Maurits van de Kamp <maurits@...> wrote: > > > Message posted by douglas roberts-wolfe <obleetorcron@...>: > > > > There is a function which will find the "zero crossing" (place where there > > is zero amplitude for the sound wave) in an audio file and automatically > > make it the border of your audio region, thereby avoiding pops and clicks > > when the audio region is played. But it seems that mine just doesn't work! > > When it is turned on, and I select a new border for the region, the border > > is not at a place of zero amplitude, and the region starts off with a pop. > > why might this be? thank you to anyone for your help > > There could be 3 reasons for this: > > First of all, since the arrange window thinks in tics and not in time, > the search zero crossing most likely only works on the audio editor > (where you can resize and move regions in the time domain, totally > independant of tempo and measures). > > Second, zero crossings only prevent pops if they come in pairs. If you > start a region with a zero crossing, it will still pop if the previous > region didn't end in one. > > Finally, if two regions overlap, searching zero crossings doesn't help > at all because the first one stops playing where the second one starts > and there is no way to be sure they _both_ cross zero there. So a > crossfade is then the only way to guarantee pop-free playback. > > Maurits. One more: if you are trying to find a zero crossing in a complex stereo file, it's sometimes impossible for the audio editor to find a place where both channels are crossing the zero amplitude line at the same time. It does the best it can, but there's always some level in one channel or the other. Sonny Keyes Ricochet Audio Toronto

AFAIK search zero crossings will work when you use the scissors tools to cut a region in two. Try making the region bigger than what you want, then use scissors to cut off the excess and delete the excess region.