Logic: Correct Timings Of Multitrack Drum Recordings

This month we show you, step by step, how to correct the timing of multitrack drum recordings using the powerful editing capabilities of Logic, as well as showing you how to make the most of your audio storage space.

There are only a very few times when technology has caused my jaw figuratively to hit the floor, but Emagic's Logic can take responsibility for one of them. I was in the studio with a band whose drummer couldn't handle the huge bass drum that the producer had insisted he use. The poor drummer was having real trouble playing consistently, and the effort of attempting to do so meant that we could only get two or three useful takes out of him per day.

The engineer had brought along a Mac G3 running Logic Audio Platinum, so he and I attempted to compile a single finished take from those that we had, and this worked fine for a while. However, there came a point at which we realised that none of the takes we had to work with were well enough in time. At this point we were clutching at straws a bit, and started looking for a way in which to improve the drummer's timing through Logic's editing facilities. After much trial and error, we hit upon a comparatively quick way of quantising the audio, across all 11 tracks of drums, with breath‑taking success. And this is how we did it...

Silence Is Golden

For the sake of simplicity here, I'll use as an example the multitrack drum recording shown in Figure 1, which comprises a stereo overhead track and a mono track each for kick and snare. However, there is nothing stopping this technique being applied equally easily to many more tracks of drums — in fact, the more individual elements of the kit which have their own tracks, the better the results will often be.

The first step in the process is to make separate audio regions for each drum hit on each of the individual tracks. Doing this by hand would be an immensely tedious job, with possibly hundreds of individual drum hits in a song. However, Logic provides a way to automate the process, in the guise of the Strip Silence facility. To isolate all the kick drums in my Kicks tracks, I simply highlighted the recorded kicks within the Audio window and selected Strip Silence from the Options menu. This brought up the Strip Silence window, which I set up as shown in Figure 2. The only value you're likely to need to alter when working with your own drum tracks will be Threshold, which should be set as low as possible, yet without causing regions to be created by spill on the track. You could also experiment with the Minimum Time To Accept As Silence, if fast individual hits aren't being picked out.

Once you have set the controls as best you can, click the OK button and then click the Replace button in the subsequent dialogue box — this will substitute the slices for the original track. If there are any series of hits that have not been successfully separated, then Strip Silence from each of these in turn until everything has been separated. Then repeat this process for the remaining individual tracks, in this case the Snares track. The result of these Strip Silence processes is shown in Figure 3.

Chopping & Changing

For the next stage in the process, you'll need to access two Key Commands. You'll need to open the Key Commands window which is available from the Settings submenu of the main Options menu. The Key Commands you need to use are Goto Selection and Split Objects By Song Position. Search for each of these by typing keywords into the Find field. When you find each one, first click the Learn Key button and then press the key to which you want to assign the Key Command. Bear in mind that you're going to need to access the commands repeatedly while simultaneously using the mouse, so it makes sense to assign them to single adjacent keys for ease of use — I used the 'Z' and 'X' keys, for example, as you can see in Figure 4.

Before you put these Key Commands to use, highlight all of the individual tracks which have been subject to the Strip Silence procedure and select Tie Objects By Length Change — this fills in the gaps in each track again now that the start of each hit has been found. If you've been careful not to move anything out of alignment, your tracks should now be sounding exactly as they were when initially recorded.

Now to use those Key Commands: highlight the first separated hit and Goto Selection. Then highlight all the drum tracks and Split Objects By Song Position. Work through each drum hit in turn in this manner, until you get something looking like Figure 5, where all the drum tracks are now split wherever there is a drum hit. However, the drum tracks should still play back unchanged. At this point I'd particularly advise saving a backup copy of the song, because the moment has now come to quantise the timing.

Highlight all the regions that have been created and open the Event List window. Click and hold on the Q button at the bottom left‑hand side of the window, and then select the most suitable quantisation grid or groove template for your needs. In Figure 6 you can see me selecting a 1/16‑note quantisation grid for my example, and this shifts all the regions accordingly, as shown in Figure 7. Because the split points are identical for each track, the audio remains in sync, even though the whole performance has now been quantised. If you play back the audio now, the timing ought to be much more accurate, though there will at the moment be gaps in the playback because of the shifting of the audio regions.

Filling In The Blanks

The final task is to cover the gaps which have been created in the performance by the timing changes. The easiest way to do this is to extend the start of each region back over the gap, and then to crossfade at the region boundaries. Fortunately, you can do both of these operations globally to save time.

Highlight all the individual regions and then zoom your Arrange window view in as far as you can on the largest gap you can find between regions. Click and hold on the bottom left corner of the object after the gap. Then hold down your Mac's Ctrl and Shift keys for fine control (Alt and Shift on the PC) and drag the beginning of the region back over the gap. However, don't stop when you've only just covered the gap. Keep dragging until you've gone about 50 percent further than you need — this will help with crossfading.

Because all the regions were selected when you modified the region's start point, you ought now to have overlapped all the regions and therefore covered all the gaps, as shown in Figure 8. Once this has been achieved, all that remains is to crossfade between the hits. With all regions still selected, click and hold on the 'Out' of Fade Out in the Parameters box, and then select the 'X' option as shown in Figure 9. Next double‑click to the right of this and enter a fade length value of around 20. The final tracks should look similar to those in Figure 10.

Now you should be able to play the drum tracks back with their new tighter timing. If there are any transitions or crossfades which sound a little unnatural then highlight the offending individual hits across all the drum tracks and tweak region start points and crossfade times for a more natural‑sounding result.

Now play it back to the band and wait for the "Wow, we really nailed that one!" Mike Senior