X‑Stream’s spectral engine may offer an unconventional control set but it is very easy to experiment with. The settings shown here reflect the finished DIY example discussed within the main text.
Create a complete musical cue from just a single sample with HALion Sonic’s spectral synth engine.
Steinberg recently improved the spectral synth engine in their HALion 7 soft sampler, and all Cubase users can get a taste of it through X‑Stream, a new, free‑to‑download (using Steinberg’s Download Assistant) HALion Sonic instrument. While X‑Stream is monophonic only, it is bound to appeal to those with a liking for ambient soundscapes and textures. It offers plenty of DIY sound‑design possibilities, including the ability to drop your own samples into the engine. To explore just what this makes possible, I decided to don my experimental media composer hat, and see how close X‑Stream could get me to composing a complete musical cue using just a single sample.
Blank & Drop
Once you’ve managed to stop playing with X‑Stream’s excellent collection of presets (it might take a while), it’s a good idea to wipe the slate clean by loading in the Init X‑Stream Layer, which is easy to find if you pick Layers as the Preset Type in HS’s MediaBay panel. This includes a default sample but, usefully, it resets the synth engine parameters to a generic starting point. With the engine thus ‘blanked’, you can drag and drop (from the Project window or your file browser) your sample of choice directly into X‑Stream’s spectral display panel. Almost any sample can be a contender, but I deliberately started with something very simple: a single note played on a synth. I’ll come back to some more colourful sample choices later. By the way, you can hear some audio examples on the SOS website, at https://sosm.ag/cubase-1024.
Need For Speed
It’s worth noting that if you click on the Spectral panel header, you toggle between compact and expanded control displays. The latter provides access to the full control set, including the full pitch, spectral filter, standard filter and amplitude envelope controls. Other panels can also be expanded into focus in the same way. I couldn’t hope to cover all of X‑Stream’s many controls here, though, so I’ll focus on some highlights that will provide a solid base for experimentation.
In its expanded view, the Spectral panel offers five sub‑pages accessed via the top‑left buttons. These include the amp envelope shown here, with suitably long attack and decay times.
The Speed control sets the speed at which the spectral engine scans across the underlying sample to create sound (100 percent is the same playback speed as the original). Changing the speed doesn’t change the pitch, but X‑Stream’s underlying time‑ and pitch‑stretching algorithms are very impressive, and it’s remarkable just how extreme you can get with the Speed control (0‑800 range) while still hearing totally usable sounds. I’m attempting to create a textural sound here, and a slower Speed setting (50 percent) seems a suitable choice when seeking longer notes.
For sustained sounds, you can define a loop region within the spectral display (just drag the left/right markers), and here I’ve set the Loop Mode to Alternate. This means the playback head moves forwards until it reaches the right loop marker and then reverses direction back to the left marker. This loop cycle is repeated as long as the note is held. As my sample contains a naturally fading sound, the slow cycling back and forth through a portion of it creates a smooth rise and fall in level that works pretty well for a sustained textural soundscape.
The Spread option, once activated, shifts the playback position between the left/right channels of your sample (it works well with mono or multi‑channel samples too), and you see two playhead cursors offset from one another when you play a note. This delivers a nice spatial enhancement even when relatively low values are used.
A Blur Of Sound
Blur Time and Blur Depth create something similar to a modulation‑based effect, such as chorus. Increasing the Blur Time gradually adds a richer quality to the sound that is very much dependent on the nature of the original sample. Blur Depth can exaggerate this, with low values remaining fairly musical and higher values moving you towards something a little more unsettling.
According to X‑Stream’s PDF manual, the Purity and Inharmonicity parameters adjust the ‘spectral purity’ of the sound. No, I’m not sure I know what that actually means either! But a quick sweep of the knobs soon gives you a sense of what’s possible. Purity seems to change the tonal character of the sound, with negative values seeming brighter and more harmonically complex, while strongly positive values seem both darker and less complex. Inharmonicity also changes the harmonic complexity, and extreme positive or negative values induce something similar to a detuning effect.
While X‑Stream is monophonic, the Stack feature provides a way to add a chord‑like element to your sound.
Well Stacked
While X‑Stream is monophonic, the Stack feature (on the right of the Spectral panel) provides a way to add a chord‑like element to your sound. Once activated, you can create a total of five layers from your core sound, with control over the relative level and pitch of each layer. Layer pitch can be specified in semitone steps within a ±36 range. You can, therefore, build a chord by specifying the required note intervals in different layers and then triggering that chord from a single note on your MIDI keyboard. And by automating either the pitch or the level of your layers you can change the voicing of the created chord.
X‑Stream offers a great selection of modulation options including the excellent step modulator, which I used to create a pulsing effect within the example sound design.I’ve done that in my examples — see the main screenshot, in which the key settings for my final patch are shown — using layers 4 and 5. Relative to the root note (pitch = 0), these layers have pitches set to +16 (a major third, one octave above the root) and +15 (a minor third, one octave above the root). By automating the level values for these two layers, you can move (or, interestingly, morph) between a more major sounding harmony to a more minor one — I did this in my example by assigning them both to the mod wheel, mapped in opposite directions, so that as one increases, the other decreases.
Mojo Filters & Mod Magic
I’ve focused on some of the more unconventional parameter options offered by X‑Stream’s spectral synth engine, but it does, of course, offer a suite of more conventional sound‑shaping tools. These include a well‑specified filter (indeed, two filters, as there’s also a spectral filter with its own envelope and presets), a multiband EQ module, and both reverb and delay modules. All can be put to good use in your DIY sound design. There’s also an amp module, and if it’s sustained soundscape/ambient sounds you are after then this is most certainly worth a visit, even if only to add some suitably slow attack and decay elements to the amplitude envelope.
As noted above, X‑Stream’s parameters can all be automated in your DAW and/or assigned for hands‑on control using a connected hardware control surface. The engine also includes two standard LFOs, an X/Y LFO and a step modulator — these can all be used to automate parameters. Right‑clicking on any X‑Stream parameter pops open a suitable dialogue box to make these assignments.
Alternatively, you can open the Matrix panel to make and/or adjust the automation settings. This provides up to 24 slots, with a huge selection of source and destination options. I used both LFOs to provide long tempo‑based sweeps on the resonance and cutoff of the main filter. The step modulator was also used to modulate the drive control within the filter. The step modulation pattern I used creates a pulse‑like effect within the sound, and I assigned a Quick Control to adjust the level of the step modulator, allowing me to blend the pulse effect in and out as required.
X‑Stream’s modulation matrix provides plenty of options for both modulation sources and destinations.
Finally for this example, as well as the stack layer automation that I mentioned earlier, I assigned the level controls of layers 2 and 3 to Cubase’s Quick Controls, allowing me to adjust the ‑24 (two octaves below) and +19 (an octave plus a fifth above) layers’ levels, to blend in these layers to change the tonal character of the overall sound in real time.
Do check out the audio examples, which illustrate just how I developed this sound from the original sample into a fully formed X‑Stream preset. I found it an interesting enough result that it prompted me to try writing a full soundscape cue (albeit a short one) using just this one sound — a totally arbitrary target, but you can hear the result in one of the examples!
One More Drop
The whole sound‑design process used here took me rather longer to explain in words than it did to actually perform. X‑Stream’s unconventional control set is, in practice, very easy to experiment with, not least because you can drag and drop your own sample into the engine. To encourage your own explorations, the last audio example includes some randomly selected samples dropped into X‑Stream and quickly tweaked based on a similar basic approach as described above. The results can be somewhat weird and unpredictable, but if you just keep dropping samples in then eventually something magical will happen... and off you’ll go exploring a new musical idea.