Nov 252011
 

This article discusses some of the popular microtuning file formats and is intended for computer musicians and composers who are using MIDI controlled virtual instruments to compose microtonal and xenharmonic music.

Microtuning Virtual Instruments – Part 3 | Formats and Features
Recently a close colleague was researching the available options for buying a portable keyboard with the requirements that it should include both a built-in synthesizer and feature full-controller, MIDI pitch microtuning. After some investigation, we discovered that there are actually no consumer keyboards currently being manufactured that meet this criteria. That’s right – as far as we could discern – there are precisely zero portable hardware keyboards being made at this moment, anywhere on the planet, that feature full MIDI pitch microtuning, and this leads to an important realization: there are currently three options for musicians and composers wishing to explore the exciting possibilities of using alternative intonation systems in their music:
1. Get into carpentry and learn how to build custom microtonal acoustic instruments, or otherwise purchase them from other builders. With the latter, for instance, there are a number of options for buying extremely high quality microtonal guitars, and or fret-boards that can be fitted to existing guitars that feature bolt-on necks, such as those manufactured by luthier and guitarist Ron Sword. Building your own instruments though can be a lot of fun, and one can be guaranteed to learn a lot about the physics of sound in the process. I would highly recommend exploring this possibility if you have access to the tools and skills.
2. Buy some of the older used hardware keyboards, such as ones previously manufactured by Yamaha, which, in their golden years, actually featured full-controller MIDI pitch microtuning. It’s perhaps the most surprising of all that Yamaha – who were previously one of the more innovative leaders in portable microtonal keyboard design and manufacturing – now offers no instruments that feature it and seem to basically only support the status quo of twelve-tone-equal-temperament hegemony. When choosing this option for microtuning, one will need a bit of luck in finding and maintaining these antique instruments, which in many cases may have been manufactured decades ago. Buying old used hardware gear that supports full-controller microtuning is something that should be approached with the greatest caution and is something that this article cannot recommend for those who are getting started with microtonal music composition.
3. Use computers and virtual instruments. It pretty much goes without saying, that as far as technological innovation is concerned, this is where the action is for xenharmonic and microtonal music creation, and there are a number of developers offering full-controller microtuning features in their software. All that is required is having a fairly current computer and a decent external MIDI controller.
The primary concern of this article is with microtuning virtual instruments that feature (what are sometimes called) microtuning tables, which essentially are lists of pitch values that the synthesizer reads in order to re-map the default pitches of MIDI Notes to other intonation systems. But it is important to not skip over the fact that there are other options available. Here is a quick overview of some of these possibilities:
1. On the Mac platform there is LMSO from developer X. J. Scott, which is used by literally thousands of musicians, composers and educators around the world, and is capable of performing dynamic microtuning using a highly specialized pitch-bend method. LMSO can also create microtuning table files for just about any microtonal synthesizer – hardware or software – that’s ever been made, and is even capable of tuning instruments which typically do not support microtuning at all.
2. Fractal Tune Smithy, from developer Robert Walker, is a program that can microtune instruments with the pitch-bend relay method and also includes many algorithmic music features.
3. Scala, from developer Manuel Op deCoul, as well as being the primary means to create microtuning format files on the Windows PC, also includes features for microtuning instruments with the pitch-bend relay method.
4. Native Instruments virtual instruments, in some cases, support microtuning features, but there is a complete lack of uniformity across their product line, with each instrument requiring its own proprietary format. For instance, as with their Kontakt sampler it is the KSP scripting language, which has the severe drawback of that some commercial sample libraries have the scripts locked where the user cannot change the intonation. Another shortcoming of KSP is that some commercial libraries also use the scripting language for changing sample articulations and in some cases may actually use specialized scripts that make changes to the intonation, such as in some of the available Gamelan libraries. Where KSP is used in these special libraries to change the underlying intonation, it may not be possible to fully re-tune them to other intonation systems without there being some conflict between using proprietary and custom microtuning scripts at the same time. It is beyond the scope of this article to detail the strange mixture of other proprietary microtuning formats that are found in the NI line, but suffice it to say that there is nothing easy about working with microtuning using their products, where every virtual instrument they offer uses its own unique method, if indeed a particular instrument features microtuning at all.
As above, our primary concern is with virtual instruments that feature microtuning tables, which, as it stands today, is one of the most popular, flexible and reliable ways to make microtonal and xenharmonic music with computers. With this method of microtuning, there are currently available three microtuning formats, all of which can be created using Scala (and or LMSO on the Mac): TUN, SCL/KBM and MTS (MIDI Tuning Standard). The below table details the features of these popular microtuning formats.
Features TUN SCL/KBM MTS Comments
Supports Full MIDI Pitch Microtuning Yes Yes Yes The Scala format requires both SCL and KBM files
for full MIDI Pitch Microtuning.
Number of Files Required for Full MIDI Pitch Microtuning 1 2 1
Real-Time Microtuning Support No No Yes Only synths that support MTS can be microtuned in real-time.
Human Readable Yes Yes No TUN, SCL/KBM can be viewed with a text editor.

TUN
Pros:
  • Virtual instruments can be fully microtuned using a single TUN file.
  • Human readable with a text editor.
Cons:
  • No dynamic, real-time microtuning.
  • To change to another intonation system, a new TUN file must be manually loaded by the user for every instrument.
Some Virtual Instruments and Developers Supporting TUN: Linplug, Big Tick, Camel Audio, AnaMark, VAZ Synths.
Scala SCL/KBM
Pros:
  • Virtual instruments can be fully microtuned using both the SCL and KBM files.
  • Human readable with a text editor.
  • The MIDI Note on which the 1/1 of the microtuning – and – the MIDI Note on which the Reference Frequency will be placed can be specified and freely changed using the KBM (Keyboard Mapping File).
Cons:
  • No dynamic, real-time microtuning.
  • To change to another intonation system, a new SCL and KBM file must be manually loaded by the user for every instrument.
  • Both the SCL and KBM files are required to do full-controller MIDI Pitch Microtuning.
Some Virtual Instruments and Developers Supporting SCL/KBM: Modartt Pianoteq.
[Note: There are other developers that have – in error – implemented only the SCL portion of the Scala format in their products, such as Cakewalk and Image Line. It’s important to recognize that virtual instruments which only use SCL, without the KBM part of the format, actually do not feature Full-Controller MIDI Pitch Microtuning. This will be discussed in more detail in upcoming articles in this series.]

MTS (MIDI Tuning Standard)
Pros:
  • Virtual instruments can be fully microtuned using single MTS files.
  • Has been a part of the MIDI Specification since the 1990s.
  • Single, as well as entire ensembles of virtual instruments, can be fully and dynamically microtuned in real-time, without the need to manually load new microtuning files by hand in the manner required with TUN and SCL/KBM.
Cons:
  • The format is MIDI data, and therefore is not human-readable.
Some Virtual Instruments and Developers Supporting MTS: Xen-Arts Xenharmonic FMTS VSTi.
j:l
 Posted by at 3:56 pm
Nov 202011
 
This article is intended for computer musicians and composers who are getting started with making microtonal and xenharmonic music using MIDI controlled virtual instruments that feature full-controller microtuning, and seeks to define what it means to be able to fully microtune an instrument to any conceivable intonation system.

Microtuning Virtual Instruments – Part 2 | MIDI Pitch Microtuning

With the profusion of alternative electronic musical instrument controllers we have available today, I’ve been compelled to consider other, and perhaps more all encompassing terms, for what many microtonal composers, theorists and musicians have long called full-keyboard microtuning. Possibilities could be something like ‘full-controller microtuning’, or even more to the point, MIDI Pitch Microtuning.
For purposes of discussion, this article will use MIDI Pitch Microtuning, or MPM, to indicate what is one of the most important features required for any virtual instrument that is intended for serious microtonal and xenharmonic music composition.
But what exactly is MIDI Pitch Microtuning?
Well, it’s very simple, and there is a strict definition for this feature…
MIDI Pitch Microtuning enables musicians and composers to arbitrarily re-tune, or microtune, each and every MIDI Note to any desired frequencies, thereby changing the underlying intonation system of the musical instrument.
Any full implementation of MPM does this by default, and with extreme high precision, is able to remap every MIDI Note to entirely new pitches – and importantly – it remaps the pitches without the need to offset or transpose the oscillators of the instrument to achieve these target pitches.
It’s important to recognize that any virtual instrument that does not meet this simple criteria of being able to arbitrarily re-tune every MIDI Note – without the need to offset oscillator pitches – does not feature, by definition, MIDI Pitch Microtuning.
In upcoming articles, there will be discussion about various popular microtuning formats, such as TUN, Scala SCL/KBM and MTS. There will also be information on how to create these microtuning files for your virtual instrument and how to use the keyboard mapping features of Scala.
Stay microtuned,
j:l
 Posted by at 10:37 pm
Nov 122011
 
This short article about pitch notation standards is primarily targeted at computer musicians who are interested in making microtonal and xenharmonic music with software plug-in instruments, and since I’ve not seen this information compiled in a concise form before on the web, I thought publishing this on Xen-Arts would be a good first step in a series of future microtuning tutorials. Very special thanks goes out to X.J. Scott for his deep insight into matters related to musical instrument intonation, and for helping to compile the lists of musical hardware and software developers detailed here.
MIDI Notes, Pitches and Notation Standards
An important foundation for making music with alternative intonation systems is having an understanding of how the pitches of 12 Tone Equal Temperament are mapped to MIDI Notes, because this is the default tuning of most software plug-in instruments and the starting point from which we will re-tune, or microtune, to other intonations.
Another dimension of the way specific pitches are mapped to MIDI Notes is considering the various Pitch Notation Standards, of which there are three in current popular usage:
1. For purposes of discussion, we’ll call the first one the MIDI Standard, which is probably the most widely used in software virtual instruments.
MIDI Standard, Middle C: C3
Range: C -2 to G 8
Middle C (MIDI Note 60) = C3 @ 261.626 Hz
Middle A (MIDI Note 69) = A3 @ 440.000 Hz
Musical hardware manufacturers, software developers and applications known to be using this standard by default:
Ableton Live
Apple GarageBand
Apple Logic
Camel Audio
Dave Smith Instruments
Linplug
Modart Pianoteq
Novation
Propellerhead Reason
Sequential Circuits
Steinberg Cubase
Yamaha
2. Sometimes (perhaps erroneously) referred to as Scientific Pitch, we’ll call the second standard ISO 16:1975, which was first proposed by the Acoustical Society of America back in the 1930s.
ISO 16:1975, Middle C: C4
Range: C -1 to G 9
Middle C (MIDI Note 60) = C4 @ 261.626 Hz
Middle A (MIDI Note 69) = A4 @ 440.000 Hz
Musical hardware manufacturers, software developers and applications known to be using this standard by default:
Casio
Cockos Reaper
Korg
Kurzweil
Roland
3. The third popular pitch notation standard we’ll refer to as the Cakewalk Standard, as it appears that this one originated with this developer.
Cakewalk Standard, Middle C: C5
Middle C (MIDI Note 60) = C5 @ 261.626 Hz
Middle A (MIDI Note 69) = A5 @ 440.000 Hz
Musical hardware manufacturers, software developers and applications known to be using this
standard by default:
Cakewalk Sonar
FL Studio
Additional comments:
1. It’s worth noting that some developers do give users the option to change to any desired pitch notation standard, a detailed explanation about which is outside of the scope of this brief article.
2. While there are three different pitch notation standards to deal with in computer music, it’s crucial to realize that the MIDI Specification of the MIDI Manufacturers Association always maps MIDI Note 60.C (Middle C) to a frequency of 261.626 Hz and 69.A (Middle A) to 440.000 Hz. Point being, no matter what note-naming convention is being used, MIDI Note Numbers always have the specific pitches of 12 tone equal temperament mapped to them by default. And understanding what this default is will prepare us for freely microtuning our instruments to other intonation systems using software musical instruments that features arbitrary MIDI-pitch microtuning (aka full-keyboard microtuning).
Below is a convenient reference table detailing the MIDI Note Numbers and their associated specific pitches from 12 tone equal temperament in Hz, the cents values, and the three above discussed pitch notation standards.
MIDI Note Number Hz Cents MIDI Standard
Middle C: C3
ISO 16:1975
Middle C: C4
Cakewalk Middle
C: C5
0 8.176 0.000 C -2 C -1 C 0
1 8.662 100.000 C#, Db -2 C#, Db -1 C#, Db 0
2 9.177 200.000 D -2 D -1 D 0
3 9.723 300.000 D#, Eb -2 D#, Eb -1 D#, Eb 0
4 10.301 400.000 E -2 E -1 E 0
5 10.913 500.000 F -2 F -1 F 0
6 11.562 600.000 F#, Gb -2 F#, Gb -1 F#, Gb 0
7 12.250 700.000 G -2 G -1 G 0
8 12.978 800.000 G#, Ab -2 G#, Ab -1 G#, Ab 0
9 13.750 900.000 A -2 A -1 A 0
10 14.568 1000.000 A#, Bb -2 A#, Bb -1 A#, Bb 0
11 15.434 1100.000 B -2 B -1 B 0
12 16.352 1200.000 C -1 C 0 C 1
13 17.324 1300.000 C#, Db -1 C#, Db 0 C#, Db 1
14 18.354 1400.000 D -1 D 0 D 1
15 19.445 1500.000 D#, Eb -1 D#, Eb 0 D#, Eb 1
16 20.602 1600.000 E -1 E 0 E 1
17 21.827 1700.000 F -1 F 0 F 1
18 23.125 1800.000 F#, Gb -1 F#, Gb 0 F#, Gb 1
19 24.500 1900.000 G -1 G 0 G 1
20 25.957 2000.000 G#, Ab -1 G#, Ab 0 G#, Ab 1
21 27.500 2100.000 A -1 A 0 A 1
22 29.135 2200.000 A#, Bb -1 A#, Bb 0 A#, Bb 1
23 30.868 2300.000 B -1 B 0 B 1
24 32.703 2400.000 C 0 C 1 C 2
25 34.648 2500.000 C#, Db 0 C#, Db 1 C#, Db 2
26 36.708 2600.000 D 0 D 1 D 2
27 38.891 2700.000 D#, Eb 0 D#, Eb 1 D#, Eb 2
28 41.203 2800.000 E 0 E 1 E 2
29 43.654 2900.000 F 0 F 1 F 2
30 46.249 3000.000 F#, Gb 0 F#, Gb 1 F#, Gb 2
31 48.999 3100.000 G 0 G 1 G 2
32 51.913 3200.000 G#, Ab 0 G#, Ab 1 G#, Ab 2
33 55.000 3300.000 A 0 A 1 A 2
34 58.270 3400.000 A#, Bb 0 A#, Bb 1 A#, Bb 2
35 61.735 3500.000 B 0 B 1 B 2
36 65.406 3600.000 C 1 C 2 C 3
37 69.296 3700.000 C#, Db 1 C#, Db 2 C#, Db 3
38 73.416 3800.000 D 1 D 2 D 3
39 77.782 3900.000 D#, Eb 1 D#, Eb 2 D#, Eb 3
40 82.407 4000.000 E 1 E 2 E 3
41 87.307 4100.000 F 1 F 2 F 3
42 92.499 4200.000 F#, Gb 1 F#, Gb 2 F#, Gb 3
43 97.999 4300.000 G 1 G 2 G 3
44 103.826 4400.000 G#, Ab 1 G#, Ab 2 G#, Ab 3
45 110.000 4500.000 A 1 A 2 A 3
46 116.541 4600.000 A#, Bb 1 A#, Bb 2 A#, Bb 3
47 123.471 4700.000 B 1 B 2 B 3
48 130.813 4800.000 C 2 C 3 C 4
49 138.591 4900.000 C#, Db 2 C#, Db 3 C#, Db 4
50 146.832 5000.000 D 2 D 3 D 4
51 155.563 5100.000 D#, Eb 2 D#, Eb 3 D#, Eb 4
52 164.814 5200.000 E 2 E 3 E 4
53 174.614 5300.000 F 2 F 3 F 4
54 184.997 5400.000 F#, Gb 2 F#, Gb 3 F#, Gb 4
55 195.998 5500.000 G 2 G 3 G 4
56 207.652 5600.000 G#, Ab 2 G#, Ab 3 G#, Ab 4
57 220.000 5700.000 A 2 A 3 A 4
58 233.082 5800.000 A#, Bb 2 A#, Bb 3 A#, Bb 4
59 246.942 5900.000 B 2 B 3 B 4
60 261.626 6000.000 C 3 C 4 C 5
61 277.183 6100.000 C#, Db 3 C#, Db 4 C#, Db 5
62 293.665 6200.000 D 3 D 4 D 5
63 311.127 6300.000 D#, Eb 3 D#, Eb 4 D#, Eb 5
64 329.628 6400.000 E 3 E 4 E 5
65 349.228 6500.000 F 3 F 4 F 5
66 369.994 6600.000 F#, Gb 3 F#, Gb 4 F#, Gb 5
67 391.995 6700.000 G 3 G 4 G 5
68 415.305 6800.000 G#, Ab 3 G#, Ab 4 G#, Ab 5
69 440.000 6900.000 A 3 A 4 A 5
70 466.164 7000.000 A#, Bb 3 A#, Bb 4 A#, Bb 5
71 493.883 7100.000 B 3 B 4 B 5
72 523.251 7200.000 C 4 C 5 C 6
73 554.365 7300.000 C#, Db 4 C#, Db 5 C#, Db 6
74 587.330 7400.000 D 4 D 5 D 6
75 622.254 7500.000 D#, Eb 4 D#, Eb 5 D#, Eb 6
76 659.255 7600.000 E 4 E 5 E 6
77 698.456 7700.000 F 4 F 5 F 6
78 739.989 7800.000 F#, Gb 4 F#, Gb 5 F#, Gb 6
79 783.991 7900.000 G 4 G 5 G 6
80 830.609 8000.000 G#, Ab 4 G#, Ab 5 G#, Ab 6
81 880.000 8100.000 A 4 A 5 A 6
82 932.328 8200.000 A#, Bb 4 A#, Bb 5 A#, Bb 6
83 987.767 8300.000 B 4 B 5 B 6
84 1046.502 8400.000 C 5 C 6 C 7
85 1108.731 8500.000 C#, Db 5 C#, Db 6 C#, Db 7
86 1174.659 8600.000 D 5 D 6 D 7
87 1244.508 8700.000 D#, Eb 5 D#, Eb 6 D#, Eb 7
88 1318.510 8800.000 E 5 E 6 E 7
89 1396.913 8900.000 F 5 F 6 F 7
90 1479.978 9000.000 F#, Gb 5 F#, Gb 6 F#, Gb 7
91 1567.982 9100.000 G 5 G 6 G 7
92 1661.219 9200.000 G#, Ab 5 G#, Ab 6 G#, Ab 7
93 1760.000 9300.000 A 5 A 6 A 7
94 1864.655 9400.000 A#, Bb 5 A#, Bb 6 A#, Bb 7
95 1975.533 9500.000 B 5 B 6 B 7
96 2093.005 9600.000 C 6 C 7 C 8
97 2217.461 9700.000 C#, Db 6 C#, Db 7 C#, Db 8
98 2349.318 9800.000 D 6 D 7 D 8
99 2489.016 9900.000 D#, Eb 6 D#, Eb 7 D#, Eb 8
100 2637.020 10000.000 E 6 E 7 E 8
101 2793.826 10100.000 F 6 F 7 F 8
102 2959.955 10200.000 F#, Gb 6 F#, Gb 7 F#, Gb 8
103 3135.963 10300.000 G 6 G 7 G 8
104 3322.438 10400.000 G#, Ab 6 G#, Ab 7 G#, Ab 8
105 3520.000 10500.000 A 6 A 7 A 8
106 3729.310 10600.000 A#, Bb 6 A#, Bb 7 A#, Bb 8
107 3951.066 10700.000 B 6 B 7 B 8
108 4186.009 10800.000 C 7 C 8 C 9
109 4434.922 10900.000 C#, Db 7 C#, Db 8 C#, Db 9
110 4698.636 11000.000 D 7 D 8 D 9
111 4978.032 11100.000 D#, Eb 7 D#, Eb 8 D#, Eb 9
112 5274.041 11200.000 E 7 E 8 E 9
113 5587.652 11300.000 F 7 F 8 F 9
114 5919.911 11400.000 F#, Gb 7 F#, Gb 8 F#, Gb 9
115 6271.927 11500.000 G 7 G 8 G 9
116 6644.875 11600.000 G#, Ab 7 G#, Ab 8 G#, Ab 9
117 7040.000 11700.000 A 7 A 8 A 9
118 7458.620 11800.000 A#, Bb 7 A#, Bb 8 A#, Bb 9
119 7902.133 11900.000 B 7 B 8 B 9
120 8372.018 12000.000 C 8 C 9 C 10
121 8869.844 12100.000 C#, Db 8 C#, Db 9 C#, Db 10
122 9397.273 12200.000 D 8 D 9 D 10
123 9956.063 12300.000 D#, Eb 8 D#, Eb 9 D#, Eb 10
124 10548.082 12400.000 E 8 E 9 E 10
125 11175.303 12500.000 F 8 F 9 F 10
126 11839.822 12600.000 F#, Gb 8 F#, Gb 9 F#, Gb 10
127 12543.854 12700.000 G 8 G 9 G 10

 

Further Information:
MIDI Manufacturers Association
ISO 16:1975

j:l

 Posted by at 4:00 pm
Jan 022011
 
Xen-Arts
presents
Xenharmonic FMTS 
An FM Synthesis VSTi For The Creation Of Microtonal and Xenharmonic Music
Xenharmonic FMTS is a 4 Operator FM Synthesis VSTi with a specialized set of features for musicians interested in exploring the expressive possibilities of microtonal and xenharmonic music making.

Microtuning Features

  • Internally loads and externally receives both MTS (MIDI Tuning Standard) Bulk Dump and Single Note Microtuning Files.
  • Operator ratios can easily be set to values that are coincident with the microtuning being used, thereby producing tuning related FM sidebands in the timbre of the instrument.
  • Isoharmonic spacing of the operator ratios.
  • Precise values may be set for microtonal pitch-bends.
  • Arbitrary microtonal period shifting makes it possible to pitch transpose in both octave and non-octave increments.

FM-RM Oscillator

  • 4 Operator FM Synthesis with Ring-Modulation.
  • 57 Operator Algorithms.
  • 11 different Operator Waveforms.

Phase & Pulse-Width Oscillator

  • 22 Waveforms.
  • Phase & Pulse-Width LFO Modulation.

Envelope Generators

  • 6 independent Envelope Generators dedicated to modulating Operators A-D, Filters and VCA.
  • Velocity sensitive.
  • Keyboard tracking.

Filters

  • 2 State Variable Filters with 12 and 24 dB response.
  • Cutoff frequencies modulated by Velocity, Envelope Generator, LFO and Keyboard Tracking.
  • Low Frequency Oscillators can be set to modulate the cutoff frequencies of the filters at audio rates, thereby producing sidebands in the signal.

Effects

  • Saturator for subtle to extreme distortion.

  • 6 dB LPF Warm Filter.
  • 4-Voice Stereo Ensemble Detuner. 

This VSTi is a gift to the xenharmonic and microtonal community, as well as to musicians and composers who are interested in exploring the exciting possibilities of microtuning in their music. It is being offered as freeware and can be downloaded here:


 Posted by at 5:16 pm