With Reason version 4 came the RPG-8 Monophonic Arpeggiator. As most of you may already know, an arpeggiator can be used to generate rhythmic monophonic melody lines out of input notes or chords. This is exactly what the RPG-8 does – and much more if you dig a little under the surface. In this article we’re going to have a look at how you can record and edit individual arpeggiated notes in the main sequencer to manually “fine tune” your arpeggio lines. We’ll also show some other cool stuff you could do with the RPG-8 – things you maybe wouldn’t consider using the arpeggiator for at first thought.

Rendering Individual MIDI Notes From an Arpeggio

A very nice feature with the RPG-8 is that it allows you to render the arpeggiated notes as individual MIDI notes. These notes can then be edited and treated just like any other recorded MIDI notes in the sequencer. Rendering individual MIDI notes from an arpeggio is made in two steps. First you have to record the notes that will generate the arpeggio, i.e. single notes and/or chords. Then, you can render separate MIDI notes from the recorded arpeggio. The following example shows how to go about it:


We have set MIDI input to the “Arp” track in the sequencer and connected the RPG-8 to an NN-19 device loaded with a percussive patch tuned to a fifth. We record eight bars with the RPG-8 in Manual Mode and 3 Octaves range. RPG8example1.rns

Now, we decide to switch Mode in the middle of the sequence to change the direction of the arpeggio pattern. We record a change of the Mode parameter from Manual to Down starting at bar 5.



Now, we’re happy with the result so far and are ready to enter step 2 – the actual rendering of individual MIDI notes from the arpeggiated notes. We make sure the left and right locators are set to span eight bars to cover the entire length of the original recording. Then, we change from the “Arp” track to the “Arp Sound” track in the sequencer. We select the RPG-8 device in the rack and use the Edit menu, or bring up the device context menu from which we select “Arpeggio Notes to Track”. Now, notes will be created on the target device track between the left and right locators.


Here comes an important thing to remember. At this point, we have two arpeggios, one coming from the “Arp” track, created by the RPG-8 and one being played as notes from the “Arp Sound” track. Before we proceed we therefore need to mute the “Arp” track. We will still keep the “Arp” track in case we change our minds later on and want to use other arpeggio patterns, ranges or directions for example.


We decide to modify some of the rendered notes to change the arpeggio “melody” a bit. We enter Edit Mode on the “Arp Sound” track and rearrange some of the notes.



Finally, to put the arpeggio line in a context, we add on a pad and a bass sound on two additional sequencer tracks.


Filter Modulation

Besides using the RPG-8 for generating melody lines, we could also use it as modulation source for modulating various device parameters. The following example shows how the RPG-8 can be used for modulating the filter frequencies of a Subtractor synth.

Here, we’re using an RPG-8 connected to the Subtractor via a Spider CV device. The Spider device is necessary because we need several CV signal outputs when we want to control the filters. We create the Spider CV device by selecting the RPG-8 in the rack and choosing Create -> Spider CV from the menu. The Spider CV device appears and is automatically connected to the RPG-8. Then, we select the “Arp” track on the sequencer and record a couple of simple chords.


Now, we want to modulate the Subtractor Filter frequencies from the Note CV signal of the RPG-8. We flip the rack around to make some additional cable connections.


Since the Note CV Out of the RPG-8 is connected to the Split A input of the Spider CV device, we connect cables from two Split A outputs to the Filter 1 Freq and Filter 2 Freq inputs of the Subtractor device. Then, we crank up the modulation knobs next to the inputs.

Don’t let the word Note CV limit your experimentation – it only implies that the output control signal level depends on current note value. The Note CV output signal can be used for controlling almost any type of parameter in Reason – not only notes and oscillator pitches.

Now, when we play back the sequence, the two Subtractor filters will open up according to the output Note CV signal from the RPG-8. The higher the Note CV out value, the higher the filter cutoff frequencies. The effect will be more significant if you choose a wide Octave range in the RPG-8 – in this example we’ve chosen 4 octaves range.


Sample Modulation

Another fun application is to use the RPG-8 for modulating sample start position. In this example we have connected an RPG-8 to an NN-19 Sampler via a Combinator device. In the NN-19 we have loaded a vocal sample which changes characteristics over time. By modulating the start position of the sample from the RPG-8 we can get really interesting rhythmic effects.


In the Combinator we have assigned Rotary 1 to the Sample Start parameter in the NN-19 Oscillator section.


If we flip the rack around, you can see that we have connected the RPG-8 Gate CV Out to the NN-19 Gate input to force it to continuously re-trig the sample. We have also connected the RPG-8 Note CV Out to the Combinator Rotary 1 modulation input and turned the modulation knob. This way we will get the Note CV signal from The RPG-8 to change the sample start position for every step of the arpeggio.


The original vocal sample sounds like this:


Like in the filter modulation example above, the modulation effect will be more pronounced if we choose a wide Octave range in the RPG-8.

Text & Music by Fredrik Hylvander