Trigger sound effects with layer markers

[Todd Kopriva]

When you have audio pops in any software, the best thing to do is to animate the audio levels from 0 to the desired volume over a very brief time (even just over a frame).

———————————————————————————————————
Todd Kopriva, Adobe Systems Incorporated
After Effects quality engineering
After Effects team blog
———————————————————————————————————

[Dan Ebberts]

It was explained to me that the chirp you hear is actually the audio playing backwards over a 1-frame period when you reset the time remapping value. You can try adding a 1-frame squelch (set audio levels to -192db) during the frame before each marker (not necessary for the first marker). I’ve had limited success with this method and it doesn’t seem well-suited for percusive sounds, because the squelch seems to bleed into the frame of the marker and kind of muffles the attack, but it might work for you.

Dan

[Charlie Aquino]

Thanks Todd and Dan.

I have managed to find a solution based on the tip you gave and did a bit of modification on the expressions being used.

I applied this expression to the TimeRemap.

len = thisLayer.source.duration;
if(marker.numKeys > 0){
m = marker.nearestKey(time).index;
if(marker.key(m).time > time) m–;
if(m > 0){
mt = marker.key(m).time;
if(time < mt+len){
linear(time, mt, mt+len, 0, len);
}else 0
}else 0
} else value;

And this similar but bit of a modified expression to the Audio Level

len = thisLayer.source.duration – framesToTime(1, fps = 1.0/thisComp.frameDuration);
if(marker.numKeys > 0){
m = marker.nearestKey(time).index;
if(marker.key(m).time > time) m–;
if(m > 0){
mt = marker.key(m).time;
if(time < mt+len){
value;
}else [-48, -48];
}else value;
} else value;

The pop is still there but barely audible. I think it will be totally gone had I realized that the audio levels can be brought down even lower than -48dB.

Thanks again.

[Tobias Beuving]

Thanks Charlie, same here with the audible click at the end of the sample, I used your modified expression for the audiolevel and now it only occurs 2% of the time, which is acceptable to me 🙂
Cheers T