Propellerhead reason assigning midi mapping combinator

Finding a set of sounds that work well together can be difficult. In Reason, it can be a laborious effort to create a combination of instruments, record some MIDI on each and then play them back. In this tutorial, we’ll look at a trick you can use in Reason to allow you to hear playback from multiple Combinators in real-time from your MIDI controller.

Reason won’t let users put Combinators inside of Combinators, most likely because this would present software stability issues. However, there are times that being able to do this, such as controlling two Combinators from the same MIDI controller, would be incredibly useful. Thankfully, there’s a way that we can achieve this.

We can change the MIDI Bus to route the keyboard input to multiple Combinators and allow them to play at the same time. It is important to know that you cannot save the setup with the Combinator patch because both involve external factors. However, you can save your project file. If you’re using the file included in the Play Pack, you will still have to configure your MIDI bus as seen in the first step below.

Step 1

The first thing that we need to do is configure our MIDI bus properly, so go to Edit > Preferences > Advanced Control.

Next, for each bus (A-D), select your MIDI controller, in my case, USB Axiom 61 ln1. This will make it so each Reason device on these bus inputs will be played by your keyboard. Close the window so we’re back at the main project.

Step 2

Now, let’s create three Combinators. Go to Create > Combinator, and do this three times.

Do you remember that really weird audio device at the very top of Reason? Well, we’re finally going to get to use it. Click the “Adv. MIDI Device” button to reveal the Reason controls for the various MIDI devices that you may have connected.

What we see now is a list of buses at the top, and below that, a list of channels for that bus.

Step 3

Now, for each bus, we’re going to assign it to a channel and a device. This will go as follows:

• For Bus A, we’re using channel 1, and assigning it to Combinator 1.
• For Bus B, we’re using channel 1, and assigning it to Combinator 2.
• For Bus C, we’re using channel 1, and assigning it to Combinator 3.

So, using the “Bus Select” button, choose bus A. Then, next to where it says “Channel 1”, click the down arrow. Use the menu to select Combinator 1 > IN.

For bus B, select bus B via the “Bus Select” button, and use the menu to select Combinator 2 > IN. Lastly, for bus C, select bus C via the “Bus Select” button, and use the menu to select Combinator 3 > IN.

Step 4

Just to test, look at your three Combinators. Then hit a key on your MIDI controller. You should see the “NOTE ON” light turn on for all three Combinators, not just one.

Step 5

To test it out further, let’s choose a sound for each Combinator. If you’re following along on what I’m doing, choose the following:

1. Combinator 1 - Pianos (Acoustic) > Distant Grand
2. Combinator 2 - SynthPoly > Velo-City Trance Lead
3. Combinator 3 - Rhythmic > Silicon Juice

Now, click record, and record a melody line. You’ll notice that the pattern is only recorded for one track. If you want it to record for all tracks, simply click the melody line, hold the control key, and move it up. This will copy it to the other track.

Reason won’t let you record more than one track at one time. However, this trick can save you significant time with mixing and matching Combinators, as you can hear them all in unison before you actually record anything. Additionally, you will hear them all playing while you record, you just have to copy the notes to the other tracks after you’re done.

Here’s my result from using this method:

Combinator 1

Combinator 2

Combinator 3

All Combinators

As you can hear, having multiple Combinators helps give more definition to the overall sound, and it allows very unique textures as you can put a rhythmic sound with a lead sound, giving it more movement. Ordinarily this would require creating a Combinator, putting all the devices into the Combinator, and then mixing it using a line mixer in the Combinator. Using this method, we just created several Combinators and mixed them using the main mixer in Reason.

You can control up to four Combinators (one for each bus) using this method, which should be more than enough for practical purposes.

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Eric Shafer is a unique hybrid of talents. A computer technology student and professional by trade, Eric also has a keen interest in graphic and web design, running his own blog, Presidia Creative. He also works extensively with music and professional audio, and has written several articles for AudioTUTS+ as well.