One use for the the ‘Time Offset’ feature in the ‘Mixer’ tab of Superior Drummer 3 is to alter the phase relationships between channels. It does this by moving the selected mixer microphone channel back in time when the slider is moved to the left. The unit of time for the movement starts in samples and then changes to milliseconds as larger movements are preformed.
The purpose of this is to artificially align the phase of an instrument in multiple channels, or even chop off the beginning transient of a channel if the adjustment is great enough. For example, when triggered, the snare drum is present in many channels (i.e. the ‘Snare Top’, ‘Snare Bottom’, ‘Overhead’, ‘Ambience’ and so on). However, due to the speed of sound (which is not instantaneous) and the varying distances of the microphones, the sound from an individual instrument will reach these microphones at different times. A good engineer will position the microphones at distances that either perfectly align or complement each other when played back together. George Massenburg did this while recording the Superior Drummer 3 library and his expert microphone placement can easily be heard by soloing a channel (the ‘Kick In’ for example) and then subsequently soloing all other channels that the kick is present in one by one. While doing this, you will notice that each subsequent channel adds to the total sound and does not create any substantial negative cancelations.
However, if you would like to phase-align instruments even closer than is possible in real life, you could adjust the ‘Time Offset’ of a more distant channel (e.g. the overhead or ambience channels). This would artificially create the effect of moving these microphones closer to the distance of the close microphones, therefore phase-aligning them (theoretically). The phase will never be 100% perfect because of the different frequency response and position of the various microphones at which the original sound was captured.
Preforming this technique with the ‘Time Offset’ feature generally makes kick and snare drums present more of their low fundamental frequency, move forward in the sound stage, and sound punchier in general. As always, it is possible to have too much of a good thing, so this technique is not appropriate in every mix scenario.
To hear this effect, you can use one of the George Massenburg presets for the Superior Drummer 3 core library. In these presets, George has already time-aligned and polarity-reversed the ‘Overhead’ channel with the ‘Snare Close’ microphone channels so that they have the closest phase relationship that is possible with this tool.
You could also download the project file for this article, as it contains a MIDI file for kick and snare that will aid in your testing. It also contains pre time-aligned overheads with the ‘Snare Close’ microphones.
To use the ‘Time Offset’ feature yourself from scratch, use good speakers or headphones and follow these steps. The effect is subtle, so a good monitoring system is 100% necessary.
1. Drag a groove that has a steady hard snare beat to the timeline, or use the one in the attached project file.
2. Solo the ‘Snare Top’ and the ‘Overhead’ channel and play the groove. You should only hear the snare drum with the included file. If you hear more than the snare, go to the ‘Drums’ tab, select the snare, and click the solo button in the ‘Level Property Box’.
3. Select the ‘Overhead’ channel (click on it).
4. Move the ‘Time Offset’ slider back slowly and listen for the spot where the low-end of the snare disappears, then leave the ‘Time Offset’ slider in this position. For the Superior Drummer 3 core library this will be somewhere between 1 and 2.5 milliseconds.
5. Reverse the polarity on the ‘Overhead’ channel. You should hear all of the low-end and mids of the snare come back. Overall, the snare should sound fuller and punchier than it did originally before the Time Offset was altered.
You could compare this to the original by setting the polarity back to normal and moving the ‘Time Offset’ slider back to zero.
A few notes and “disclaimers” for the phase gurus out there 😉
- This technique will not result in perfect phase alignment across the entire frequency spectrum, as that is impossible when using audio from two different microphones in two different positions. While it won’t be perfect, many users will like the effect of using the ‘Time Offset’ tool.
- This tool is best used to align the snare in the ‘Overhead’ mic to the ‘Snare Close’ microphone. Toms are positioned at different distances from each overhead microphone therefore, using this technique will not work perfectly with Toms and it will likely have negative consequences for the kick or snare.
- ‘Time Offset’ is used per channel. This means that you must choose on a channel by channel basis the main instrument to which you would like to align the distant channel. For example, you could align the ‘Overhead’ channels to the ‘Snare’ and the ‘Ambience Ribbon’ to the ‘Kick’ channels.
- As you will notice with the George Massenburg presets, this particular goal (phase alignment) works best with the overheads and snare. Close phase alignment does not work nearly as well with more distant ambience channels due to their drastically different envelopes and frequency response. However, in practice it can still provide useful results.
- Drum position. ’Time Offset’ works on a very small scale. Therefore, a setting that works to align the overheads to one particular snare drum may not work for a different snare in the same library. This is due to the thicknesses of the drums and their relative distance from the overhead microphones. The close snare microphones were positioned at an optimal distance to each new snare drum recorded in the kit, on the other hand the overheads do not move as to not disrupt the balance in the rest of the kit. Simply put, every time you change snare drums you will need to re-adjust the ‘Time Offset’ for the new snare.