energyXT is a multiplatform DAW - digital audio workstation which runs under Linux, MacOSX and Windows. Along with Renoise and Ardour it is for sure one of the most mature Linux application for creating / mixing audio.

Korg nanoKontrol is a simply MIDI controller and belongs to nanoSERIES.  Works perfectly as 8 channels controller (volume of every channel + mute / solo buttons).

Unfortunately, they don't work together out of the box - unfortunately Linux version is a bit cut off when comparing to Windows one (there is still no proper Jack support, MIDI support still needs improvment and no VST version of application). However it is possible :).

First of all, for today (13th of February, 2011) latest stable (2.5.4) version has broken support of MIDI. If you want to play with MIDI controllers, you have to download beta version, which has this bug fixed: http://www.energy-xt.com/beta/.

You can find description of this problem here:

http://getsatisfaction.com/energyxt/topics/midi_control_not_working_in_2_5_4

Next, you need an alternative Jack driver for energyXT with extended MIDI support: http://sourceforge.net/projects/libaam-jack/files/1.0/.

After download unpack archive and execute make command inside created directory. Created file libaam.so copy to your energyXT directory (yes, you will overwrite default one).

Another necessary utility is a2jmidid, it allows you to expose ALSA based MIDI interfaces in Jack environment:

$ a2jmidid
JACK MIDI <-> ALSA sequencer MIDI bridge, version 6 () built on Thu Jan  1 01:00:00 1970
Copyright 2006,2007 Dmitry S. Baikov
Copyright 2007,2008,2009 Nedko Arnaudov
Bridge starting...
Using JACK server 'default'
Hardware ports will not be exported.
Bridge started
Press ctrl-c to stop the bridge
port created: Midi Through [14] (capture): Midi Through Port-0
port created: Midi Through [14] (playback): Midi Through Port-0

After it you can route your Korg controller into energyXT, first route it into MIDI Trough IN:

and next route MIDI Trough into energyXT (you need alternative Jack driver, described above to make it working):

With this setup you can finally run energyXT and use below energyXT tutorial to play with your controller: