Despite its age, Logic’s EXS24 sampler is still an essential part of the Logic workflow and a dependable instrument to have at your disposal. Its strength is undoubtedly the speed at which you can map a variety of samples in seconds. When it comes to sound design, though, it starts to show its age. Wouldn’t it be good if Logic had a more ‘creative’ sampler? Something where the samples only formed the starting point of your creative process?
In truth, Alchemy’s sample-playback engine is as powerful as the EXS24 (although, to be fair, the mapping system is not quite as user-friendly), but when it comes to processing those samples – using a range of filters, modulators, effects and granular processing – it far outshines the EXS24. Indeed, as we’ll see in this workshop, Alchemy could easily become your first choice over the EXS24!
Alchemy patches use a total of four Sources – A, B, C and D – that can be thought of as four oscillators. As well as holding a sawtooth or square wave, Alchemy can import a series of mapped samples into a Source. The mapped samples could be a series of one-shot, velocity-switched drum samples, for example, or a collection of multi-sampled pad sounds spread across the full range of the keyboard. As each Source has its own sample map, Alchemy instantly trumps the EXS24 in its ability to have four discrete layers in a single patch.
Alchemy’s Import Audio feature doesn’t quite match the EXS24’s ability to import and map samples, so if you’re after some complicated mapping options, I’d stick to the EXS24. Instead, Alchemy’s Import Audio feature is a quick-and-easy way of importing audio files into the synthesis engine, which is perfect for a few drum samples, like those illustrated in the walkthrough, or some basic multi-samples. One key concept to grasp as this point, though, is that the samples can be imported using a series of different modes – Additive, Spectral, Granular and Sampler.
Once the sample data has been loaded into a Source, we can start to get creative. The key signal-processing features to note are that the playback engine has two separate multi-mode filters as well as four independent effects busses (A, B, C and D) and a Main effects bus. The immediate creative task is to think about how each of your four Sources could use these features, maybe routing groups of Sources through different filters, for example, or using a different effects block for each Source.
The walkthrough illustrates some examples using drum samples, but there are any number of interesting options to explore outside of this, especially when you start to also add in the possibility of including modulators (like LFOs and step sequencers) to control these signal processors.
One of my favourite creative applications of Alchemy is the Granular Engine, which is one of the alternative ways you can import and manipulate sample data. Imported in as a Granular sample, Alchemy can perform a number of unique tricks in relation to ‘freezing’ the sound.
Rather than simply playing back the sample data sequentially, the Granular mode sees the sample data as a series of sound grains, each lasting no more than a few samples. By repeating these grains, a sound can effectively become frozen in time, or you could slowly move through the grains to produce a wavetable-like sound. As the walkthrough illustrates, this can sound great on drums, particularly for glitch-like treatments in harder forms of electronic music.
Beyond the EXS
Like many people, I had initially overlooked Alchemy’s ability to work with samples in favour of the more tried-and-tested working environment of the EXS24. While I would always favour the EXS24 for more complicated mapping tasks, Alchemy clearly comes out on top when it comes to sonic mangling.
Purely on the filtering alone, for example, the EXS24’s paltry six filter types look almost insignificant compared to the dozens of filters included in Alchemy. Tellingly, this walkthrough only just scrapes the surface of what can be achieved with samples in Alchemy, but it’s a good springboard for further exploration and, most importantly, a good grounding in its principal sonic architecture.
Alchemy – Logic’s secret sampler: step-by-step
1. Start with an initialized patch (File>Initialize Preset) in Alchemy. Click on the Saw label to open the drop-down Source menu, where you can select the Import Audio option. You should now be presented with a file browser.
2. Navigate to the location where you’ve copied the workshop folder from the DVD. Drag the included samples over to the Dropzone and order them as you want them to be arranged on the keyboard, starting from C1.
3. Before you press the Import button, ensure you’ve set the Analysis Mode to Sampler and set the Mapping option to Drum. Once this is sorted, press the Import button to have Alchemy map the samples.
4. By default, Alchemy has a sluggish attack time (0.1s) that kills the transients on the kick and toms. Reduce this to 0.0s so that the sample’s attack is preserved. You could also try creatively adjusting the envelope.
5. Move out of the Global view to see the individual controls for the Source. We need to change the Source from being Mono (note the circle icon to the left of the Edit button) to the interlinked Stereo option.
6. Pressing the Edit button brings up the Sample Mapping screen for the Source. Note the series of Zones (one for each drum sample) positioned consecutively from C1 on the keyboard. Highlight the Select By MIDI option.
7. Each Zone has its own set of associated parameters, including a Volume, Tune and Pan control. Try panning the three toms across the soundstage, and experimenting with different tuning on the kick drum.
8. Try some creative applications with layered Sources. From the Source menu, select Copy Source which will place all the samples with their mapping onto the clipboard. In Source B, select Paste Source.
9. Our aim here is to differentiate different samples between the two Sources. Open Source A’s mapping window, select the snare on D1 and then hit Delete to remove the Zone.
HIT REVERSE A Reverse button is found on the right side of the window. Pressing it will reverse the playback of all the samples in the Zone. Copy an existing Source, but then reverse the duplicate layer. In the case of drums, you’ll then have them being triggered in both directions!
10. Repeat the same process on Source B, but this time delete all the other Zones, leaving just the snare Zone on D1. Play back the included drum sequence and notice how the two Sources are triggered at different points.
11. Let’s look at the routing on the Global page. The two Sources can be routed to their own filter (F1/F2) using the control to the right of pan. Route the second filter to FX A using the drop-down Routing option.
12. Open the Effects tab at the bottom of Alchemy. On FX A, configure a delay (set to dotted 8th and 1/16th) followed by a reverb. Because of the routing, these effects are solely applied to the snare.
13. The main effects are applied to the kit as a whole, including the processed snare. In this case, we’ve applied the Phat Compressor to lock the sound on the drums together and add some extra weight.
14. We’re going to use Source C to apply some granular treatments to the drums. Use Import to load 808 samples as before, although this time select Granular for the Analysis mode and Drum for the Mapping option.
15. Either Solo Source C or deactivate the other Sources. Set Source C to Stereo mode and playback the sequence. At the moment, the Granular version doesn’t sound greatly different to the conventional sample playback.
16. Change Speed to 0%. The drums are now ‘frozen’ in time with the first few sound grains repeating indefinitely. Try increasing RPan so that the grains are distributed across the soundstage, creating a granular shimmer.
17. If you want to control the length, consider mapping an envelope to Source C’s volume. Click on the Volume control, then from the drop-down menu, select AHDSR Env>New AHDSR. Reduce the sustain accordingly.
18. Return to the Global view and balance the effect. The Granular version shouldn’t dominate the sound. You could also delete selected Zones (such as the kick) so that they’re not subjected to the Granular treatment.