Documentation updated 24. Jan 1997 from BeriSoft Cooperation

>>>> Problem: Wrong frequency of absolute midi notes

All (!) versions of ERTS until Jan97 (V3.21) calculate
the frequency of absolute midi note (octave = 0) wrong
because they do not recognize the zero value of the
octave value. The result is that absolute midi notes
are calculated just like octave/midi values.
The formula is Octave * 12 + Note + 11.
E.g. octave=1 note=1 becomes a 24 absolute midi note.

Because absolute midi notes are converted according
to this formula by mistake, they are 11 notes too high.
E.g. midi note 75 would be presented as 86=0*12+75+11.
In other words, instead of 622 Hz it would be 1175 Hz.

Although this difference seems to be quite obvious
and far beyond the JND threshold this error was not
detected before now. Thank you to Johannes Schaefer
and his colleagues, Clinical Psychology department
at the Technical University Dresden, Germany.

>>>> Work around:

1) Patch your ERTS*.EXE files by
   getting the FIXMIDI patch procedure from
   ourworld.compuserve.com/homepages/Berisoft

Suggested steps for FIXMIDI procedure:

   Optional: Demonstrate the error by performing step 5

   1: Download FIXMIDI.EXE via WWW into your ERTS system directory
      where the ERTS system files are located (typically C:\ERTS).

   2: Run FIXMIDI to self-extract archive

   3: COPY ERTS*.EXE ERTS*.MID  (This is your backup copy)

   4: Run FIXANOTE.BAT

   5: Run the TESTMIDI ERTS-script to compare absolute and relative
      MIDI tone definitions within ERTS.

      For German version   ERTS testmidi /d
      For English version  ERTS testmidi /Tt

In case of any problems or questions contact {support} @ erts.de