notes.txt:Added notes.

doc/notes.txt

 
 ** use Log frequency frequency transform instead of FFT.
 
-** Add a 'write' preset file button.
+** Add a 'write' preset file button - so the preset file can be saved prior to next crash.
 
 ** measurement values can generate MAX_DBL - be sure that are not being sent through to the audio algorithm.
    (see ln:965 cmDspKr.c for a hack to fix this)
 
 ** add begining and ending measure numbers to 'seq' labels
 
-** Gain compensation form mode 4.
+** Gain compensation fore mode 4.
+
+** Do IFFT using cos()^c + i * sin()^c - these bases are orthognal but cause harmonic distortion.
+   To be efficient this might involve writing an FFT function.
 
 Seq 2  m24 Mark 36 & 38 
 Seq 4: Mark 115