This article is the follow up to the first part of the Fundamentals of Sampling series where we touched on the basic principles and concepts of digital sampling. This part will focus on more advanced and technical aspects of sampling along with some practical uses derived from them.
Start & End Points
The start and end points of a sample determine its playable range on a DAW or sampler in a non-destructive way, allowing us to use different sections of a sample without having to do any permanent edits on an audio editor. The start point defines the point where the sample will start playing, whereas the end point defines where it will stop. Most professional DAWs, as well as some advanced samplers like Kontakt, allow the start and end points to snap to a musical grid, which makes it possible to make changes to them while keeping the loops in sync with the host tempo.
The start point is particularly useful to shape the sound of a sample, as it allows us to remove transient content as well as the low frequency information that resides at the beginning of the sample. This can be very useful to create thinner and more delicate variations of a sample that can provide a big deal of detail in our mixes and beats and go a long way in genres like Ambient, Chill, Lo-Fi Hip Hop and Downtempo.
Playback modes control the way a sample is played back on virtual instruments. Some of these modes determine the direction in which the sample will play once it’s triggered, including forward and reverse. When the sample is looped, the forward and reverse modes can be combined and alternated in a single mode that allows the sample to be played forwards and backwards within the area defined by the loop. Also, with granular synthesis, it’s possible to trigger samples from numerous start points in rapid bursts and combining multiple playback modes.
Some advanced synthesisers such as VPS Avenger and Reaktor Form even allow users to create custom playback modes with graphic editors that enable the creation of automation curves to control the playback speed and direction of the sample in real time. These playback editors turn playback modes into a dynamic feature, as opposed to the traditional approach of defining them as a static setting, enabling stunning time based effects such as stuttering, time stretching and scratching.
Looping is the ability to loop over a sample. This feature works differently depending on whether we use it on a DAW or in a sampler. On the former, the loop function allows us to stretch the sample beyond its original length and have the sample loop for as long as we stretch it. On a sampler, it allows us to loop over a sample for the entire duration of the MIDI note that is triggering it.
Looping enables many creative possibilities when applied to one shots, allowing us to create rhythmical patterns whose speed is determined by the length of the loop. With this technique, it’s possible to make entire loops with a one shot sample and a single MIDI note.
Another interesting way of taking advantage of the looping feature is to set up various loop ranges among different instances of a sample, which allows us to deconstruct samples into smaller loops that can provide variation to the full length sample.
Envelopes are modulation sources capable of shaping samples over time through the adjustment of several breakpoints called stages. Envelopes can be applied to all sorts of controls on a sampler, but they are specially useful when applied to the amplitude, since that allows us to shape how the volume of a sound develops over time.
The most common and primitive form of envelope is the ADSR envelope generator, which was created by the American engineer Robert Moog in the 60s. ADSR envelopes feature four stages called attack, decay, sustain, and release capable of shaping common parameters such as volume, pitch and filter cutoff in a very fast and convenient way.
Recent developments on digital technology and software have made possible a more advanced type of envelopes called graphic, parametric or multi-stage that take advantage of the flexibility and power of digital graphical interfaces to provide a visual feedback on the envelopes shape, as well as the possibility to create and delete stages, define the time span of the envelopes, and make them snap to a grid in order to allow for the creation of rhythmical envelopes synced to the host tempo.
Here concludes this two parts article on sampling in which we have learned several features of this vital music production field and some of their practical uses. We learned about start and end points and how they can be used to trim samples as well as more advanced uses of the start point in the context of sound design. Then we touched on playback modes in different applications like DAWs, and samplers and how some advanced synthesisers are revolutionising this feature. After that we moved onto looping, and how this feature can be harnessed to achieve very creative and interesting results with loops and one shots. Further down, we delved into envelopes, stressing their remarkable power and usefulness when it comes to sound shaping and sound design.