SP2. Drum Processing.
Below is a preview of my drum track.
After recording my drum track, I then set out to process the drums by adding; HPF (High Pass Filtering), Compression, Time Adjustment and then implemented a certain technique used by producer Trent Reznor by adding distortion to a drum track. This creates a big, crunching beat, best heard between 0:00″- 0:15″ of the track The Line Begins To Blur, as shown below!
No.1 – High Pass Filter (HPF).
As with the first studio project, I began the processing of my drums by introducing HPF to rid the track of any unwanted sub-bass frequencies added by the room it was recorded in. Below is an example of how this filter was applied, this time, to my snare drum track.
The snare drum has a steep cutoff of around 24dB per octave to make sure that all stray, low-end frequencies have been removed, although for the snare in particular, I wanted to keep as much of the 150-200Hz punch (that occurs in most live snare drums) as possible, so the cutoff point has been set to around 140 Hz to leave in that little extra power behind the snare.
No.2 – Time Adjustment (Sample Delay).
Whilst recording my drums, I needed to compensate, again, for the time of arrival difference between the more closely mic’d drums, i.e. the snare and kick, to the AKG’s which recorded the whole kit. The difference was around 102 samples. This was done by zooming in on the track regions, highlighting the gap between the first signal start point and the last, which in this instance happened to be the AKG that was positioned over the snare and Hi-Hat. This value, as before, was then inserted into the Time Adjuster plugin on all drum tracks, except for that mic and also the two ambient mic tracks. The reason for not wanting to delay the time of the drum tracks to match the ambient mics (which had by far the longest time of arrival difference) is because, as well as the colouration that a different room gave to the sound of the drums, the delay between the signals of the kit and ambient mics arriving at the control room helped to add to the overall flavour of my drum track. Below is screen shot of the highlighted drum tracks (Oversnare and undersnare mics on top, slower kit mics on the bottom) and the Time Adjuster plugin on the Kick drum track.
No.3 – Compression.
For this second project, have chosen to use the same set of guidelines for the compression of my drum tracks. I found the effect of these guidelines in my last project to be satisfactory enough in the processing of my drums. Below is a screen shot of the Compressor/Limiter plugin used on all of the drum and percussion tracks (shown in this instance on my kick drum track) as well as the guidelines that correspond to them. (note: Some parameters of the compression plugin have been altered to taste and may appear different to the guidelines stated below.
Drum Compression Settings.
- ATTACK = 5 milliseconds.
- RELEASE = 10 milliseconds.
- THRESHOLD = -15dB.
- RATIO = 5:1 to 8:1.
- KNEE = Hard.
No.4 – Distortion.
As mentioned previously at the beginning of this post, I am trying to emulate the production techniques used by Trent Reznor on the processing of his drums in the track The Line Begins To Blur. To create that distorted, crunchy drum sound, I have used the Sansamp guitar amplifier modelling plug-in with a distortion preset. The use of guitar amp modelling is another technique used by Reznor, although he tends to use this for his guitar tracks. The reason for me using this plugin to effect my drums is that it gave me the colouration I was looking for. This was implemented by sending all of the drum tracks down a bus to a mono auxiliary track carrying the distortion plugin. This meant I can adjust the amount of signal sent to the distortion plugin from each drum track. Below is a screen shot of the inserts and sends of two of the drum tracks showing the bus that these tracks were sent to, as well as a screen shot of the Sansamp plugin including the parameters that were used to distort my drums.
I found the outcome of this very successful because it did not over-distort the drum track, yet still added enough crunch to get the effect I was aiming for.
No.5 – Quantization.
Because my drums were not in time with the click track, I needed to quantize them by either using ‘Elastic Time’ adjustment (used on guitars, see guitar processing post) or by selecting around four bars from the whole recording that I found to be roughly in time and then going to ‘Event – event operations – quantize’. This then allows you to choose the beat resolution to which the processor quantizes the audio, of which I selected between 8/16 note.
No.6 – Audio Reversing.
When recording my drum track I did not manage to get any crash cymbal crescendos that could be used to lead into a chorus for example. To solve this I adopted a production technique used by George Martin i.e. reversing audio. I wanted to replicate a crash cymbal crescendo, so I created a copy of a cymbal region, selected it, then went to ‘Audio suite – other – reverse’ and then hit ‘process’,which then reversed my crash cymbal audio (a technique used later on the vocal tracks, see vocal processing post). This was then butted-up against the original crash region to create a swooping in-and-out cymbal movement. Below is a screen shot of the reverse processing engine and the reverse/normal crash audio regions in the arrange window of Pro Tools.