SamplecrazeStretch That Note

Drum sound processing

The Sounds

In dance based music the choice of drum sounds is critical, and we have come a long way from processing live, acoustic kits into workable sounds that can live alongside a fast and driving BPM (beats per minute). Instead, we use drum samples and, in many cases, layer these samples with other samples and acoustic sounds. In the case of urban music, and the more defined and extreme sub-genre Hip Hop, we tend to go with samples from famous drum modules and drum samplers like the Emu SP1200, Roland TR808/CR78, and the MPC range—most notably the earlier versions such as the MPC60/3000.

The drum samples that we layer and process within a beat must meet very specific requirements. These include: topping and tailing, mono/stereo, acoustic/noise/ tonal, and pitch/duration specifications. Let me briefly explain, ahead of the longer discussions later in this book:

• Topping and Tailing: This process entails truncating a sample (removing dead space before and after the sample) and then normalising it (using Peak Normalisation to bring the sample’s amplitude/level up to 0dB). We do this for a number of reasons. Crucial considerations include sample triggering, aligning samples on a timeline, and referencing gains within a kit or beat.

• Mono/Stereo: A drum sample that displays the same information on both channels is a redundant requirement unless the dual channel identical information is required when layering using the ‘flip and cancel’ method. (Watch my video Art of Drum Layering Advanced, or read the article I wrote for Sound On Sound magazine entitled ‘Layers of Complexity’ for more information.) The only other instance where a stereo drum sample would be used is if the left and right channel information varies, as would be the case if a stereo effect or dynamic process were applied, or if the sample were recorded live using multi microphones, or if we were encoding/decoding mid/side recordings with figure-8 setups. We try to keep kick samples, in particular, in mono. This is because they remain in the centre channel of the beat and, ultimately, the mix. For other samples like snares, claps, and so on, stereo can be very useful because we can then widen and creatively process the sample to taste.

• Acoustic/noise/tonal: Acoustic drum sounds will invariably have been tuned at the playing and recording stages but will need to be re-tuned to the key of the track in which the beat lies. Tonal drum samples, like the legendary 808 kick drum, will also have to be tuned. More importantly, the frequency content of the sample will determine what type of dynamic processing can be applied. A sine-wave based tonal kick will have no harmonics within the waveform and will therefore be reliant on innovative dynamic processing techniques. Noise-based samples contain little or no tonal information, so require a different form of processing because the frequency content will be mainly atonal.

• Pitch and Duration: Ascertaining and tuning atonal drum sounds is a nightmare for many, and this area is covered extensively in later chapters using specific tools and processes. Extending duration with pitch changes, altering pitch without altering duration, using time-stretching, and modulating pitch and/or duration using controllers and automation: all these are excellent forms of pitch manipulation.

Extract taken from Beat Construction book.