What for and how ?
Mad Harry's MIDI Enhancer
In the 18th century the equal tuning of musical instruments won
through against the meantone tuning and against natural scales. Those
sounded better but had a major disadvantage: they only allowed making
music in a subset of the 12 keys. If you wanted to make music for
example in F#, and your piano was tuned in C, you had to retune each
single key before playing. Of course, most people restricted
themselves to few keys, wherein their instruments sounded good. If you
are a musician, you surely know the story about J. S. Bach's
"wohltemperiertes Klavier" ...
The MIDI Enhancer allows you to tune your instrument while
you play it ! Or another musician can tune while you play. The tuning
is done by a single key press.
The MIDI Enhancer therefore needs 2 input sources (via 1 MIDI
- the notes played on the input channel(s) are modified
with tuning information in the harmonizer and forwarded to up to 16
- the note played on the control channel (which
normally is not an input channel) determines the tuning of the notes
appearing on the output channels.
The MIDI Enhancer herefore can be operated in 2 different modes:
- Pitch Bend. Notes are put out always on all enabled
output channels, but per output channel at most 1 note at a time can
be on. Therefore a maximum of 16 notes can be played simultaneously,
the exceeding ones are lost. Why ? Because the MIDI Enhancer
individually tunes each output channel by a different pitch bend. Each
of the up to 16 output notes gets its individual pitch bend. The MIDI
pitch bend information is common for all notes on a certain MIDI
channel. So for e.g. 4 notes with different micro tuning you already
need 4 separate MIDI channels. In pitch bend mode the pitch bend range
must be adjusted to -100..+100 cent on each output channel. The MIDI
Enhancer tries to set this up by sending pitch bend sensitivity
messages. If your device does not understand these messages, you have
to set it up manually.
- Scale Tune. GS compatible instruments understand so-called
scale tune messages, thus allowing to adjust the pitch of each of the
12 notes with one single MIDI message. Advantage: the MIDI Enhancer
works mainly transparently. A synthesizer connected to the output of
the MIDI Enhancer will behave rather similar as without MIDI Enhancer.
It will not limit the number of notes sounding simultaneously.
The most important differences between the 2 modes:
| ||Pitch Bend||Scale Tune|
|Tuning Range||-100..+100 cent||-64..+63 cent|
|Accuracy||1.56 cent||1 cent|
|Message Size||3 byte per note||22 byte per scale|
|Program Changes||replicated per outp. ch.||transparent|
|Bank Selects||replicated per outp. ch.||transparent|
|Controller Changes||replicated per outp. ch.||transparent|
|Pitch Bend Messages||thrown away||transparent|
|Pitch Bend Range||-100..+100 cent||arbitrary|
|Sound||all outp. channels equal||arbitrary|
|Latency||not hearable||in automatic mode|