Using Arpache

 By John Walden

It's so easy to reach for the same audio plug-ins time after time - but MIDI plug-ins such as Arpache can bring something different and shouldn't be overlooked.

Given the extensive and sophisticated audio-processing functionality provided by all modern DAWs, it can be easy to overlook the powerful creative options offered by their less glamorous MIDI features, particularly MIDI plug-ins. So this month we'll concentrate on a couple such plug-ins — Arpache 5 and its more advanced sibling Arpache SX — and explore how you can use them to breathe life into your project.

Arpache 5

I don't know which wag at Steinberg came up with the name Arpache for the arpeggiator plug-in, but I'll set Shadows jokes aside for the moment (the editor has threatened me with something unpleasant if I stray too far into that territory...).

Although they may look simple, Arpache 5 and Arpache SX are both capable of producing excellent results. I'll start with Arpache 5, and as the PDF Plug-in Reference manual does a reasonable job of describing the basic controls, only the briefest of recaps is required here, before we move on to consider what it can bring to your music.

Arpache 5 with a setup suitable for a basic up-and-down arpeggio.

The Quantize, Length and Semi-Range settings define the basic properties of the arpeggio. Quantize controls the bar divisions at which the arpeggio notes will appear, with 32nd notes producing something quite manic at all but the slowest tempos, and a value of 1 producing one note from the arpeggio each bar. Both dotted and triplet versions are available for all time intervals between these extremes. The Length setting controls the length of the notes in the arpeggio. If note lengths are kept short (16th or 32nd settings), an almost staccato feel is created regardless of the synth sound source being used. At longer note lengths, the nature of the MIDI sound source is more significant, as the sustain and decay properties of the patch might come into play. Experimenting with the relationships between the synth sound and the Length setting can produce some interesting variations, although things can get a little OTT if you combine a short Quantize setting, a long Length setting, and a sound source with lots of sustain. Finally, the Semi-Range setting simply defines the range of semitones from which notes for the arpeggio will be taken, relative to the position of the lowest note being played.

The top three buttons in the Playmode section are straightforward, setting the sequence of notes in the arpeggio to play either up, down or up and down. The lower buttons are rather more interesting. The '?' button simply randomises the arpeggio note order. Depending upon the sound being used, this can create a nice variation on the straight-up or straight-down patterns. Perhaps more useful is the Order On button: with this engaged, the note order of the arpeggio is defined using the Play Order facility, which allows a sequence of up to eight notes to be specified. The number relates to the MIDI notes being played into Arpache 5 via the MIDI track, starting with the lowest note. In Play Order mode you can create some almost riff-like progressions (which work well for the usual mid-range keyboard parts) but it's also easy to create interesting bass lines.

Experimentation is the name of the game here, as it can take some time to work out just how the various controls interact with each other. Fortunately, for the Play Order mode there is a small number of presets for users to explore — and you can also save your own patterns as presets.

Wot, No Electro?

Of course, nobody would want to use Arpache 5 to create something suitable for a synth-based dance track... would they? Oh, alright then, if you want to, you can create the classic (clichéd?) synth chord patterns that will return you to a land of '80s pop, or place you very firmly into certain styles of dance music. Basic Apache 5 settings aside, all this requires is a suitable sound source, and the Halion One patch 'Polymood' makes a decent starting point — though there are plenty of other preset sounds in the various Cubase 4 VST instruments that you could put to good use.

Play Order mode offers more control over the form of the arpeggio created by Arpache 5.

There are also some less obvious applications for Arpache 5. For example, used with a suitable bass pad-like sound, a combination of slow Quantize (such as a setting of 4 to produce quarter notes) and a Length setting of 1 (so that each note in the arpeggio sustains for a whole bar) can be used to generate a drone-like bass part, which will have some nice timbral movement as the sustained notes are brought in and out of the arpeggio. Used with the right sound source (for example, Halion One's 'Close To The Edge' patch) and at a suitably slow tempo, this can be made to sit anywhere between a melodic bass pad and sound design. You could also add in some atmospheric percussion (such as the 'Storm' style from Groove Agent 3) — and things can start to get quite scary!

In fact, Arpache 5 can be very effective with percussive and drum sounds, so let's look at two examples that provide a useful way of exploring this.

First, try a percussive synth sound using your VSTi of choice (the 'Djembe+Marimba Layer' patch in Halion One would be a suitable starting point) and, with a medium-to-slow tempo (70-90bpm), set a Quantize value of 16 and Semi-Range of 12 (the Length setting doesn't make any difference with this kind of sound). It is then a case of experimenting with the Playmode settings. Although the most interesting effects can be created by using the Play Order options, even a simple up and down configuration can produce some interesting rhythmic effects. By gradually adding and subtracting notes from the MIDI keys being held, you can change the rhythmic feel, adding movement and dynamics to the performance.

Exactly the same process can work equally well with straight drum-kit samples, and any GM-based drum kit could serve as a starting point. You're unlikely to come up with a traditional rock or pop drum-pattern using this method, but for a more abstract or experimental piece the approach can generate plenty of interesting material.

SXing Things Up

Arpache 5 has been around for a considerable time but (fortunately) Steinberg retained it when they introduced Arpache SX, as Cubase moved into its SX era, and both these plug-ins have been preserved in Cubase 4.

It doesn't have to be just dance music: here, Halion One is providing a bass synth pad via a slow arpeggio from Arpache 5. I've also added atmospheric drums from Groove Agent, to create a rather unsettling feel!

In terms of basic operation, the two are similar, but Arpache SX replaced the Play Order options of its predecessor with the more sophisticated SEQ mode. Again, the basic use of each control for Arpache SX is described in the Plug-in Reference PDF.

What this PDF doesn't do such a good job of is illustrating the potential of SEQ mode. The key creative element of this mode is the ability to define aspects of the arpeggio from an existing MIDI phrase. This is best done by recording a short phrase (one, two or four bars usually works best) into a MIDI track. This phrase is then simply dragged and dropped onto the box in the lower-left corner of the Arpache SX window.

Depending on how the various settings are then configured, selecting SEQ mode allows the relative pitches, velocities and timing of the notes in the MIDI phrase to control how the arpeggio is created by the plug-in. It is also important to note that the number of different MIDI note pitches within the dropped phrase can have an influence upon how Arpache SX works its magic — and a phrase with a larger number of MIDI pitches will produce more complex (and more unpredictable) arpeggios. If you want to explore this further, simply drag and drop a suitable MIDI phrase, select SEQ mode as the Arp Style, and then work through the steps described below.

If Quantize is set to Source, then the timing of the notes in the arpeggio is taken directly from the MIDI phrase, and if the MIDI phrase contains 16th notes, it may produce a fairly standard-sounding arpeggio pattern. However, if the sequence has a few 'missing' notes in an otherwise 16th note pattern, a more interesting rhythmic element is created in the arpeggio. Incidentally, the Quantize value can also be set to something other than Source while in SEQ mode — this simply forces the pitch pattern contained in the dropped phrase onto a regular timing grid defined by the Quantize setting.

The Arpache SX plug-in offers plenty of flexibility via its SEQ mode. A MIDI phrase can be dropped into the bottom-left box to provide the arpeggio source.

The pitches of the arpeggio that's created depend on the Trigger Mode setting, and it is here that the number of different pitches in the dropped MIDI phrase interacts with the number of different MIDI notes being held as a chord and fed to the Arpache SX input. Let's consider an example where the dropped phrase contains five different pitches, but only a three-note chord is being played into Arpache SX to drive the arpeggio. Arpache tries to match the pitches of the MIDI input to the relative pitches of the dropped phrase. If the number of pitches is not the same, then the plug-in needs to know how to deal with that and the Trigger Mode setting provides it with that information. If, for example, we wanted to create a more traditional arpeggiator-style result, the Sort First setting would provide a good starting point: as there are fewer MIDI notes being input than there are different pitches in the dropped phrase, the first input note is used repeatedly to fill in the gaps in the matching process — and this note therefore appears more frequently in the arpeggio. In contrast, if the Sort Normal setting is used, Arpache SX only matches pitches up to the number of input notes: no notes are substituted to fill the 'missing' pitches and, as a result, there are some gaps in the arpeggio. This isn't necessarily a bad thing, as it can create some unexpected and often interesting rhythmic effects.

As a quick aside here, if Trigger is chosen as the Trigger Mode, then Arpache SX simply triggers the original phrase contained in the dropped MIDI part. If just a single MIDI note is played into Arpache SX to create the arpeggio, this will be used as the root note for the dropped phrase, and when you play a different single note it will simply transpose that phrase. This provides a very simple way of triggering and transposing a riff, and it is also an obvious candidate for bass-line construction.

The upper track, containing chords, was used to create an arpeggio with Arpache SX. The lower track shows the result of applying the Merge MIDI In Loop process. This new MIDI part can then be edited and brought back into Arpache as required.

A final touch of dynamics can be added via the Velocity Source buttons. The three available options — SEQ, Input and Fixed — are fairly self-explanatory. In Fixed mode, the notes of the arpeggio all have the same velocity, and this obviously tends to produce a fairly static (in terms of volume dynamics) output. In SEQ mode, the velocity of the notes in the dropped MIDI phrase controls the velocity of the same steps in the arpeggio, and by editing the note velocities before dropping the phrase into Arpache you're able to add some very controlled volume dynamics — and considerable rhythmic interest — to the resulting arpeggio. With Input as the Velocity Source, the volume dynamics are controlled by the velocities of the individual notes being played into Arpache SX and, again, this allows the player to add some real dynamics to their performance.

Although there's plenty of fun to be had by dropping any old MIDI phrase into Arpache SX, perhaps a more obvious (though no less interesting) way of using the SEQ mode is to import a MIDI element from elsewhere in your project to use as the arpeggiator source — and a short MIDI bass line or drum phrase can work very well here. The result is a synth arpeggio that is, in some way, rhythmically linked to the source phrase. This can be really effective in helping to generate a tight musical groove, while achieving an arpeggio with a much less 'robotic' feel.

Look What I Played!

Between them, the Arpache 5 and Arpache SX arpeggiators offer a bewildering array of possibilities that could be used in your projects, but occasionally there are times when you can't quite get the result that you want from them.

Trigger Mode influences how Arpache SX deals with matching the number of different pitches contained in the dropped phrase to the number of pitches in the chord arriving at the MIDI input. This setting can produce some interesting variations in the resulting arpeggio.

For example, perhaps you've got a great result, except for a few problem notes that simply don't work in the context of the musical arrangement in which the arpeggio is being played. Fortunately, it is possible to transform the output from either plug-in into a conventional MIDI part, containing all the notes from the arpeggio, and this part can then be edited using Cubase's standard MIDI editing tools. Whether you simply need to remove the odd note that is surplus to requirements, or change note velocities to control the volume dynamics, this means that you have complete control over the final performance.

To do this, you need to use the Merge MIDI In Loop function. First, you solo the MIDI track that contains the MIDI part you wish to process. The Left and Right locators must then be set around this part (if you select the part and then press 'P', which is the 'Locators To Selection' key command, the locators will automatically be placed around it). The MIDI / Merge MIDI In Loop menu option will then bring up a small dialogue box, and if you tick the 'Include Inserts' and 'Erase Destination' options Cubase will obligingly replace the existing MIDI part (which will usually be the chords you are using to drive Arpache) with the actual notes that have been created by the arpeggio process — very neat! Once you're done with processing, though, make sure you deactivate the Arpache plug-in on the track, or you'll find yourself facing arpeggiated mayhem! 

Published January 2008