microtuning MIDI

Scala by Manuel Op de Coul

Scala is a powerful software tool for experimentation with musical tunings, such as just intonation scales, equal and historical temperaments, microtonal and macrotonal scales, and non-Western scales.”

Scala is hugely powerful with MIDI and microtonality.  A number of 3rd party developers have since written scripts and applications to further apply the Scala’s use.  The downside?  It’s difficult and time-consuming to install, and even once it’s installed you must take some time to learn its command-line interface—but it’s time well spent if you’re looking for alternate tuning and working with MIDI.  I’ve designed this post as a simple procedural checklist for any composer who wishes to run Scala on their computer.

Scala is available on Windows, Linux and Unix (Mac) systems.  The installation on a Mac does however require some command-line commands and configuration that may be somewhat unfamiliar to the average Macintosh user.


Step zero: Read Scala’s installation documentation:


Detailed installation procedure for installing Scala on Mac OS X, including Mountain Lion:

Step One = BACKUP!
I highly recommend Carbon Copy Cloner for all your backup needs.  Among many powerful features,  CCC will make an exact “carbon copy” of your computer to an external drive.  This way,  even in the event of a total data loss you can boot from your backup drive an escape crises unscathed.

2) Download and Install the latest version of XQuartz (aka X11) here:

3) Download and Install XCode from Apple, the one that is appropriate for your version of Mac OS X. This requires registering with Apple as a developer. Make sure to choose the version with “Mac Dev Center”.
Also ensure that you leave the option for “UNIX Development Package” selected when installing.

4) Download and Install MacPorts:
Choose the download option that’s appropriate for your operating system.

5) Open up Terminal.  Go to Applications -> Utilities -> Terminal
(or press Shift-Command-U in Finder for a shortcut to Utilities).

5a) From the Terminal, copy/paste or type in the following code:

sudo port install fontconfig
And then wait patiently while it installs.

5b) Remaining in Terminal, copy/paste or type in the next code:

sudo port install gtk2

Then wait even more patiently!  This is a large install of the GTK+ toolkit and will take several moments.  There will no progress bar, but trust that even when things appear to slow down, the developer packages you downloaded are being installed in the background. If you’re paranoid, open up Activity Monitor in Utilities and observe your CPU and Disk Drive working hard.

5c) If you’re running Mac OS X 10.6 you might need to upgrade gtk2 to enforce compatibility for 32bit and 64bit applications.
Copy/paste this command into the Terminal:

sudo port upgrade --enforce-variants gtk2 +universal
This will re-install and upgrade these components, and will likely take well over an hour.

6) Download and Install Simple Synth
(This will be used for testing purposes in order to make sure everything is working when Scala is up and running)

7a) Download Scala!
Create a folder and name it “Scala” in your Applications Directory.  Drag the Scala.app into that folder.

7b) Download Scala’s Scale Archive
*DO NOT double click to open this .zip file – Leave it “Zipped Up”  If your browser unarchives zip files automatically, delete the folder it automatically creates and just keep the “scales.zip” file.  Drag this .zip file into the Scala folder you just created in the Applications directory for easy access.  Here’s a listing of the contents within the Scales Archive:  http://www.huygens-fokker.org/docs/scalesdir.txt

8) Open Audio MIDI Setup in Applications/Utilities.  Go to the Window Menu and click “Show MIDI Studio”
Double click on IAC Driver and make sure “Device is online” is checked.

9) Read this: (It’s affectionately called “Scala for Dummies”)
Also be sure to follow the tutorial within Scala itself for further orientation.

10a) Do some more test-driving: Open up Simple Synth, then open up Scala.
Load or create a scale as highlighted in the link above.  Click “play” on Scala’s toolbar to see a virtual MIDI controller.  Here you can map any scale to your controller.  Click on “Select” and choose a layout system fit for your scale.

10b) Set the MIDI input of Simple Synth to the IAC Driver Bus
-set the MIDI output in Scala.  Go to Relay -> Sound Settings and select IAC Driver Bus as the MIDI output.
-in the Relay settings window, select your MIDI keyboard or controller as the MIDI input device*
*in order for Scala to “listen” to your MIDI controller, you must enable “Start Relaying”.

Scala’s routing will generally look something like this:
MIDI input
(from either a file or a controller) -> Scala -> Synth, Sampler, or DAW etc.
The routing is all virtual – internal via the IAC Bus – to/from software of your choice.  For instance, in Pro Tools or Logic you may select a MIDI track to listen to the microtonal pitch adjustments of Scala by selecting the IAC Bus as the input on any MIDI track!

Powerful 3rd-party software helpful in harnessing the power of Scala in your workflow:
-Custom Scale Editor by H-Pi Instruments: http://www.h-pi.com/CSEsoftware.html
-A Scala scale browser by H-Pi Instruments:  http://www.h-pi.com/ScalaVistasoftware.html
-Scala2Kontakt* http://www.12equalboresme.com/Scala2Kontakt/index.html
*This is a windows application, but can run successfully on a Mac via CrossOver, and it’s very powerful for working with custom tuned scales in Kontakt. (If using this via CrossOver, be sure to install a WinXP bottle with the NET 2.0 Framework!)

Also, here are a few great virtual instruments that load Scala files directly:
MachFive 3
Szforzando (free!)

There are many more 3rd party, Scala-compatible tools being developed all the time!  Here’s another list of compatible 3rd party software:

Other resources to check out:


Posted Monday, December 13th, 2010

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