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1998-03-14
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********************************************************************
* *
* S H A R E W A R E *
* *
********************************************************************
MIDI Enhancer V1.0 User Manual
==============================
Introduction
------------
The MIDI Enhancer allows you to play microtonal music on a
conventional synthesizer supporting the MIDI poly mode (multi mode).
It also allows you to play microtonal music in a band of MIDI
instrument players with one "harmonizing" player.
Copyright
---------
All rights reserved. The MIDI Enhancer V1.0 must not be used
without payment of the shareware fee to
Harald Wolfgang Rieder phone: Germany - 089 3159 7200
Am Stutenanger 11d
D-85764 Oberschleissheim
Legal stuff
-----------
USE THIS PROGRAM AT YOUR OWN RISK! The author assumes no liability
what-so-ever for any damages that may result from using this program
or its accompanying files. This program includes absolutely no
warranty, written or implied.
What for and how ?
------------------
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 cable):
- the notes played on the INPUT CHANNEL(s) are modified with tuning
information in the harmonizer and forwarded to 16 output channels.
- the note played on the HARMONIZING CHANNEL (which normally is not
an input channel) determines the tuning of the notes played on the
input channels.
The output is always done on all 16 MIDI channels. On each output channel
a maximum of 1 note is sent. Therefore a maximum of 16 keys can be played
simultanously, the exceeding ones are lost in the harmonizer.
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.
Delivery
--------
You should have the following files:
MIDIHANC.APP
or
MIDIHANC.GTP: the program.
MIDIHANC.PAR: parameter file. Contains all your settings and the
tuning information. Should initially be the same as
ORIGINAL.PAR.
ORIGINAL.PAR: parameter file. Contains the tunings described below.
MDHC_ENG.DOC: this user manual.
MDHC_GER.DOC: German user manual.
You might have:
DESKTOP.CFG: automatically generated, don't care
Setup
-----
Copy at least MIDIHANC.APP/GTP and ORIGINAL.PAR to the desired
directory. Then rename ORIGINAL.PAR to MIDIHANC.PAR.
Connect the MIDI output of your keyboard to the MIDI input of your
computer. Split your keyboard. It must be able to send on 2 different
channels. Or use any 2 MIDI instruments and a MIDI mixer.
E.g., if you send on channels 2 and 8, select channel 2 as
harmonizing channel and channel 8 as input channel, or vice versa, in
the controller window. Do not switch the harmonizing channel as an
input channel.
Connect the MIDI output of your computer to the MIDI input of your
synthesizer. Your synthesizer must work in the poly mode, receiving
on all 16 MIDI channels. Select the same sound on each MIDI channel.
The pitch bend range on each channel must be +- 100 cent, if you want
to use ORIGINAL.PAR. This means that, if you'd play a D, you could reach
a C# or a D# with the pitch bend wheel.
Using the MIDI Enhancer
-----------------------
0. Theory
1. General
2. The Tuner Window
3. The Controller Window
4. The Monitor Window
0. Theory
- - - - -
Well sounding intervals (from now own called "distances") consist of
notes with frequencies in a simple ratio, for example the octave
(from now on called 10) consists of tones in the ratio 2/1.
Other good sounding ratios are 3/2, 4/3, 5/4, 6/5, 7/4, 7/5, ... .
A bad sounding frequency ratio is, for example, 40/27.
The most convenient today's "well tempered" tuning uses the ratios
2^(1/12), 2^(2/12), 2^(3/12), ...
for building distances. 2^(3/12) you find between C and D#, or between
D and F, for example. Actually, besides the 10s with its ratios of
2^(12/12) = 2/1, there are now other rational distances, but only
irrational ones.
From now on the notes are called by numbers in this document:
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' C := 0 '
' C# := 1 '
' D := 2 '
' D# := 3 '
' E := 4 '
' F := 5 '
' F# := 6 '
' G := 7 '
' G# := 8 '
' A := 9 '
' A# := A '
' H := B '
' '
' This makes things much simpler. The distance between a D and an F'
' now is the distance between a 5 and a 2, i.e. 3. '
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Pythagoras is supposed to have invented the pythagoraen tuning. Beginning
from any special note, all other notes are derived by 7s (quints):
1 -> 8 -> 3 -> A -> 5 -> 0 -> 7 -> 2 -> 9 -> 4 -> B -> 6
"->" means, that right and left notes have a ratio of 3/2.
For the 7s the ratio 3/2 is used. Thus you are lead to tunings like
the following (f means any fixed frequency):
0 = 1/1 * f
1 = 256/243 * f
2 = 9/8 * f
3 = 32/27 * f
4 = 81/64 * f
5 = 4/3 * f
6 = 729/512 * f
7 = 3/2 * f
8 = 128/81 * f
9 = 27/16 * f
A = 16/9 * f
B = 243/128 * f
This pythagoraen tuning has a "woolf's 7" between 6 and 1. Besides that,
it sounds very similar to the equal spacing used today.
With polyphonic music coming up more and more, a more sophisticated
tuning was invented: the clean tuning. Beginning from any special note,
all other notes are derived by 7s and 4s:
9 > 4 > B > 6
^ ^ ^ ^
5 > 0 > 7 > 2
^ ^ ^ ^
1 > 8 > 3 > A
">" means 3/2.
"^" means 5/4.
Thus leading to tunings like:
0 = 1/1 * f
1 = 16/15 * f
2 = 9/8 * f
3 = 6/5 * f
4 = 5/4 * f
5 = 4/3 * f
6 = 45/32 * f
7 = 3/2 * f
8 = 8/5 * f
9 = 5/3 * f
A = 9/5 * f
B = 15/8 * f
This tuning contains many beautiful ratios, but you must not go away
too far from the 0. The MIDI Enhancer enables you to walk far away and
stay in a clean tuning by simply choosing a new fitting harmonizing
note !
1. Gerenal
- - - - - -
The MIDI Enhancer saves all important settings on exit into
- MIDIHANC.PAR, if you started MIDIHANC.APP by double cklick.
- any other parameter file, if you started MIDIHANC.APP by dragging
this parameter file onto its icon.
Since it is an ACS program, you can load ACS modules with the usual
mechanism.
2. The Tuner Window
- - - - - - - - - -
Here you set up the tunings of the 11 distances in relation to the
harmonizing note. Pitch bend information is sent out to modify the tuning
separately on each MIDI channel. Pitch bend messages consist of 2 bytes
(a data byte is 7 bits in the MIDI world). If you set up your synthesizer
as described above, a single pitch bend step should be 1/(64*128) * 100
cent. Unfortunately most synthesizers through away the least significant
data byte, thus leading to a pitch bend granularity of 1/64 * 100 cent.
(This is still good enough for defining better distances with the help of
the tuner.)
The tuner has two step sizes: +- 1 and +- 128. If your synthesizer does
not evaluate the least significant data byte, only use the ++ and --
buttons, not the + or - buttons.
The pitch bend values for the most important distances d are given here:
d note difference exact rounded (dividable through 128)
2/1 10 +-0 +-0
9/5 A +1441 +1408
7/4 A -2554 -2560
5/3 9 -1281 -1280
8/5 8 +1121 +1152
3/2 7 +160 +128
7/5 6 -1433 -1408
4/3 5 -160 -128
9/7 4 +2874 +2816
5/4 4 -1121 -1152
6/5 3 +1281 +1280
7/6 3 -2714 -2688
8/7 2 +2554 +2560
You can define up to 4 tuning tables. Each table may be named.
All buttons can also be reached from the keyboard, pressing additionally
the Alternate or the Control key if needed.
3. The Controller Window
- - - - - - - - - - - - -
You can select one or more of the 16 MIDI channels as input sources,
which will be summed up and will togehter be modified by the harmonizing
channel. Only one channel can be harmonizing channel. The harmonizing
channel should not be an input channel, however, for first experiments
you might do so.
The tuning table you already chose in the tuner window. With the
pythagorean one you might hear no difference to before, except one ugly 7
for example. With the clean tables you might feel, that some major and
minor chords sound compact and good, others not. All the new distances and
chords might sound quite unused to your ears.
If you want to play a piece in a well-defined key, you can select a key
in the key field. Valid keys are 0,1,2,3,4,5,6,7,8,9,A or a, B or b.
Other characters mean "no key selected". You need not to select any key.
The MIDI Enhancer will then work in an "integrating" mode.
Harmonizer Modes:
If "hold" is checked, always the last harmonizing note played on the
harmonizing channel will be hold. If it is not checked, you
can switch off the harmonizer by not playing any notes on the harmonizing
channel.
- Choose a table with clean tuning (in the tuner window).
- Do not enter any valid key.
- Do not check "hold".
- Press the "start" button !
Play a major 0 chord on an input channel. It should sound as usual.
Now additionally play a 0 on the harmonizing channel. Do you hear the
difference ? A major 7 and a major 5 will sound like the major 0.
Play a major 2 together with a 0 harmonizing note. Doesn't this sound
ugly ? You have to reharmonize by playing e.g. a 7, then the major 2
sounds good again. Try a little bit !
Stop the harmonizer by any key press (on the computer keyboard).
If you want to enter a certain key, you need some experience. A 0 should
be the best choice for most major 0 pieces. For a minor 0 piece, a 9 might
be the better choice. Don't worry, if you have to learn when and how to
change the harmonizing note.
For the MIDI experts:
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' With the controller 16 on the harmonizing channel you can select a '
' tuning table, with the controller 17 you determine the key. Thus, '
' you need not to stand up and walk to your computer. '
' Program changes and foot switch controller changes appear replicated'
' on each of the ouput channels. After one program change command the '
' MIDI enhancer will change all your 16 synthesizer sounds. '
' Continous controllers' granularities are first reduced by the MIDI '
' Enhancer and then the fewer controller change commands are forwarded'
' to all 16 output channels. Thus, all controllers will work, but not '
' as fine as usual (due to MIDI performance reasons). '
' Pitch bend will not work. In principle it would be possible, but '
' it is not yet implemented. '
' The same is valid for channel pressure. '
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
4. The Monitor Window
- - - - - - - - - - -
If you do not trust the MIDI enhancer, open the monitor window. It will
monitor the harmonizing note and the pitch bend offset. The pitch bend
offset is added to all notes equally. If it enters a critical range
(which can lead to errors), it will be inverted.
It also shows you MIDI errors that ocurred. If you play very fast (many
notes together) and/or send many controller changes, it's easy to produce
errors. The limiting piece is the MIDI output interface of your computer.
The MIDI Enhancer in general produces more MIDI messages on its output
than it receives on its inputs. If on the inputs events appear with maximum
MIDI speed (~19000 baud), the output will already be overloaded.
HISTORY
=======
V1.0 first public release
----