No midi

[Mehmet Okonsar]

Hello users and creators of the best music notation program in the world!
As always I have a simple question:

in a file setup like this I have no midi output, no matter where I do
put the \midi block..:
where can I put the \midi block?

%---------------------------------------------------------------------
\version "2.7.10"
\include "english.ly"

\header {}

atonicKey =
  #(def-music-function (parser location) ()
     #{ #(ly:export (make-music 'EventChord
                     'origin $location
                     'elements (list (make-music 'KeyChangeEvent
                                      'tonic (ly:make-pitch -1 4 0)
                                      'pitch-alist '((4 . 5)
                                                     (5 . 5)
                                                     (6 . 5)
                                                     (0 . 5)
                                                     (1 . 5)
                                                     (2 . 5)
                                                     (3 . 5))))))
        \set Score . extraNatural = ##f #})

unmeteredOn =
    {
        \set Timing.measureLength = #(ly:make-moment 1 4)
        \set Timing.automaticBars = ##f
    }
\score {
\new PianoStaff {
    \unmeteredOn {
<<
    \context Staff = "RH"
    {   \atonicKey
        \clef treble
% ---> rh notes here <---
c''1

\bar "|."
    }
    \context Staff = "LH"
    {   \atonicKey
        \clef bass
% ---> lh notes here <---
c1

\bar "|."
    }
>>
}
}
%====================================================================== LAYOUT 
BLOCK
\layout
{
    indent = 2\cm
    \context
    {
        \Staff
            \remove "Time_signature_engraver"
    }
}

%===================================================================== PAPER 
BLOCK
\paper
    {
        #(set-default-paper-size "a4" ) % ----- set other formats here

    }


------------- 
Best regards,
Mehmet Okonşar, pianist-composer
www.okonsar.com
address@hidden