Introduction to Samplers: DIY Sampler Instrument

Introduction

A sampler is an electronic or digital musical instrument, in some ways similar to a synthesizer. However, instead of creating new sounds through waveform generating oscillators, samplers play back pre-recorded sounds of instruments, voices or any other sound loaded into them. In the case of digital samplers these sounds are converted to digital information in the form of binary code and controlled through MIDI, which in turn can be modified and edited after recording. These sounds are usually stored on a hard drive or hard disk and are triggered by pressing a key or drum pad on the sampler.

The sampler is therefore a useful tool that gives a musician almost unlimited access to instrument sounds, without having to actually own the physical instrument itself, thereby making music creation cheaper and easier than before. In addition to this, the creation of the sampler allowed for more accurate and even “perfect” musical compositions and performances, made possible through Midi Editing features such as “quantize”- for off time playing and “swing”- for drum sections lacking groove. Sampler instruments also allow for more creativity by allowing the user to control various aspects of the sound such as pitch, resonance, filter cutoff and much more. These features are especially useful for producers of electronic music genres as well as sound designers.

Before we begin, it must be said that an important part of creating quality sampler instruments lies in the editing of the samples. Audio editing can mean anything from compression to volume changes, but in this case I am specifically talking about “cutting” the audio samples into separate parts.
All audio (sampler or not) should be “cut” at “zero crossings” (regions of no sound in the audio signal) and not where there is a peak or trough (areas where there is sound) in the wave. Doing this will help ensure there are no clicks and pops in your audio, which are of course to be avoided at all costs. This should be your first concern when working with audio samples. You can then use whatever other editing techniques and effects to get the best out of your audio, but make sure your cuts are clean and do not have any clicks, pops and other unwanted artefacts.

In this tutorial we will be editing and sampling a well-known and used drum break, from the song “Impeach the President” by “The Honeydrippers”. The drums are played by Roy Charles Hammond, better known as “Roy C”. After editing we will then load our samples into Logic Pro’s EXS24 Sampler Instrument.

Let’s begin!

1.) Import an audio track. This can be done by simply dragging and dropping your chosen sample(s) from its source into an empty audio channel. In this case the file in question was taken from a “drum break” file on a hard drive.

2.) Identify the section(s) that you want to work with. I like to do this by setting the track locators on the section I want to use then creating a loop. In this case it’s a 1 bar loop, with 9 individual drum hits.

3.) Zoom into the audio track to get a closer view of the audio signals waveform. You'll notice that the signal goes up (crests) and down (troughs) and has a middle point where the crests and troughs meet. These middle points are called “zero crossings” there is no sound at these points. Your task is to identify where these middle points are, and only cut at said zero crossing points.

If you cut at points that have either a crest or trough you will create a click or pop in your sample. Clicks and pops in audio samples are often undesirable, so always cut at zero crossings to avoid audio “artefacts".

4.) Select your scissor tool, and begin editing your audio samples. Remember to only cut at “zero crossings”. The two images below show what a bad edit with cuts made on a crest look like vs. a good edit cut made at zero crossings.

5.) Continue editing the rest of your audio samples into the individual parts you desire. In this example there are 9 individual hits: Kick, Hi Hat, Snare, Hi Hat, Double Kick, Open HiHat, Kick.

The screen shot below shows what your completed audio edits should look like. Notice that each individual transient hit is cut at the beginning and at the end. At this point you can also delete all the audio that you didn't need or use.

6.) Now we can create our sampler instrument. To do this, simply select and highlight all your edited audio samples, right click with the cursor over the highlighted audio and select “Convert to New Sampler Track”

7.) After following step 6, a block will pop up allowing you to name your new instrument, select which keyboard key your samples will start on and control note velocity. Make the necessary changes if you want to. But be sure to keep the “Regions” option selected otherwise Logic will create the sampler instrument through its transient marker detection, rather than your own edits.

It’s a good idea to just keep all the default settings as they are. You can always come back and try different settings once you're more familiar with creating sampler instruments. If you're happy with your settings, go ahead and click “OK”.

8.) You should now have a playable MIDI instrument that plays the samples you edited and loaded. If you press a key and don't hear any sound make sure your keyboard is in the right octave. If not, use the transpose key to get down to the correct octave and key.

Your screen should now look something like the screen shot below. That is, you should have a muted audio track of your original audio edits. Below it you should have a MIDI sequence of the edits you made, playing through your new EXS24 sampler instrument.

9.) You can go ahead and delete your original audio edits, as well as the automatic MIDI sequence that was loaded up. You're now ready to begin recording and creating your own MIDI sequences using your new sampler instrument.

After your sampler instrument is named and saved you can use it whenever you need that particular instrument sound in the future.

Conclusion

An added benefit of using a sampler is not only that it allows you to have the rarest of instruments just a click away, but also that sampler instruments will usually have features that allow for more experimentation and creativity by the user. Logic Pro’s EXS24 sampler makes this possible by incorporating synth-like components into its sampler features, allowing the user to play around with various components such as Filter Cutoff, ADSR, LFOs, Pitch and Glide, which can all be patched together and modulated just like a synthesiser, thereby making it a useful tool for getting out musical ideas, in sound design and of course for full scale music productions.

You should try out some of these features and apply the knowledge you have learned from synthesisers to create more interesting and altered sounds. You can find the necessary information on synthesiser components and what they do in previous Music Journal articles. As usual, I hope this tutorial was helpful, and until next time…