Pro Tools features the ability to quickly edit and clean up your recordings using the “Strip Silence” feature. What it does is similar to a noise gate, but it has a couple extra things that make it easier to work with as well as more flexible.
Strip silence is most commonly used on drum tracks such as the tom/floor tom tracks. This is because they are not continuously played, yet they add to the overall “noise floor” of the drum recording without often adding much to the tonality of it. When you record drums and you spend all your time tweaking the snare track EQ and compression and gate and reverb and everything else, and then you just bring up your tom track with all the un-affected snare bleed, it somewhat negates the benefits you might have gained with processing. It is like distilling something, then adding water back into it.
So here we are with a regular old multitrack drum session. You can see that rack tom 2, 3 and the floor tom all have some action on it in the middle of the timeline, but all that bleed can sometimes just add yuck. Normally ambiance is a good thing, but in this scenario, the ambiance that these tracks leave is colored with the resonant ringing of the tom itself overtime any other piece in the kit is played. It is like pitched reverb. Well if we want an up front sort of sound, we can cut this out manually, or better your use “Strip Silence”.
1. First select the region that you want to affect.
2. Press “Command+U” Mac or “Control+U” PC to bring up the strip silence window. It is also near the bottom of the Edit menu.
3. There are a few parameters to work with. The Strip Threshold is the volume limit where you say, “Everything below this volume can get deleted.” This takes a little finesse to get it right but the beauty is that Pro Tools visually shows you the regions that will remain after you strip the silence, so you can keep adjusting it until it looks right. The Minimum strip duration just dictates that strip silence will omit anything within this window of time that is above the threshold from being stripped. It is like the hold parameter of a gate. The region start and region end pads make sure that there is some audio before and after whatever is above the threshold once things get stripped. This allows you to have a very short segment which can then later be faded in or out so that the trimmed region doesn’t abruptly start and stop.
4. So in the Picture below, you can see that I have selected the audio region, and adjusted the Strip Threshold to only be alerted when something above -16dB happens. There is a small pad on the beginning and end as well. I like to try to get the end pad to coincide with the next hit in the track, that way if I don’t get around to fading this region out, it won’t end as abruptly with the other hits coming in.
5. The last picture shows the region after I have pressed the “Strip” button in the strip silence window. Now the audio track has been trimmed and we are all set to do the same steps with the other tracks.
What is nice about strip silence versus a gate is that you can preview the segment before any processing has happened, and you can always manually move a couple region starts and ends if you to. Since it breaks up the region into sub-regions, you can see if there are any “false-triggers” and manually go in and delete those regions.
This technique can really help clean up drum tracks and make them less washed out. Also, the less bleed you have, the less phase issues you will have to deal with, which typically means a much better sound. You can also use this technique with spoken word, say a podcast, or something where you might only want to remove the portions where there is silence, then consolidate the talking or music.