SeaGL

11:30 Friday 11/08/24

GNU/Linux Loves All

Chorals

Ode to Creative Commons
A Protector of Free Information

Plugin Unplugged

Ode to GNU General Public License
A Protector of Free Technology

About FLO Software

What is FLO Software?

FLO Software or Free Software is software that respects and supports a user's freedoms and Human Tech Rights. Free Software is different than freeware, which is typically proprietary softare that is gradis but not free as in freedom. Proprietary freeware, as opposed to Free Software, still comes with a price. That price is your Human Tech Rights.

What are our Human Tech Rights?

Every human has a right to
- privacy
- security
- repair
- internet
- education
- speech

Human Tech Rights and music technology should not be mutually exclusive.

We use GNU/Linux, the greatest operating system of all time, to make great music.

Skip-fretting

Matthew Autry discovered skip-fretting more than a decade ago. It is a microtonal guitar fretting that allows you to play in larger edos such as 41edo and 72edo. Every fret is a multiple of edosteps. Matthew has made instruments in 41, 53, 65, 72, 87, 118, 130, and 183 edo. Skip-fretting is a revolutionary music technology which is FLO and not patented.

What is a Kite guitar?

A Kite guitar is a guitar with a skip-fretting Kite Giedraitis discovered in 2019. It is a 41edo skip-fretted guitar from 20.5edo fretting. Each fret is 2 edosteps. This layout makes 7-limit harmony easy to explore. 7-limit serves as a gateway to higher prime limits and other edos. Kite-tuning is FLO and not patented.

Skip-tuning

What is an edo?

Edo stands for equal division of the octave. An octave, a 2/1 frequency ratio, is the simplest frequency ratio after the unison, a 1/1 frequency ratio. 12edo, or standard tuning, is the most common tuning. In the edo, every frequency ratio besides octaves are irrational numbers. The oldest known reference to an equal division is ed4/3 written about by Aristoxenus. He divided 4/3 into 30 parts. This is essentially 72edo.

In 12edo, a 3/2 ratio has an error of 2 cents. This means that a 3/2 ratio approximated in 12edo has an error of 2 parts per 1200 in relation to the octave.

What is a cent?

A cent is one edostep from 1200edo. It divides a halfstep into 100 parts. A halfstep is one edostep of 12edo.

What is microtonal music?

Microtonal means tuning in a way that deviates from standard tuning (12edo). Though 12edo is a great technology, a tone by itself does not conform to this system. A tone makes harmonics which are integer frequency multiples of the fundamental. Standard tuners are not set up to show these harmonics. All sound and music beyond a single sine wave is in fact microtonal. In the harmonic series, Do Re Mi most simply corresponds to 1/1, 9/8, 5/4. These ratios can be expanded to 8/8, 9/8, 10/8.

There are many different ways Do Re Mi can be tuned. Here are the simplest and most common ways to tune Do Re Mi. The notes are given as frequency ratios relative to Do.

tuning	Do	Re	Mi
standard	2**(0/12)	2**(2/12)	2**(4/12)
Ptolemaic	8/8	9/8	10/9
Pythagorean	64/63	72/64	81/64
reduced	Do	Re	Mi
standard	1/1	2**(1/6)	2**(1/3)
Ptolemaic	1/1	9/8	5/4
Pythagorean	1/1	9/8	81/64

Harmonics to Standard Tuning with Cents Deviation

>>> from xenedoji import *
>>> A2 = Pitch('A2')
>>> A2 * 2
A3
>>> A2 * 3
E4 +1.96c
>>> A2 * 4
A4
>>> A2 * 5
C#5 -13.69c
>>> A2 * 6
E5 +1.96c
>>> A2 * 7
G5 -31.17c
>>> A2 * 8
A5

Same thing with Hertz

>>> Pitch(Hz(110))
A2
>>> Pitch(Hz(220))
A3
>>> Pitch(Hz(330))
E4 +1.96c
>>> Pitch(Hz(440))
A4
>>> Pitch(Hz(550))
C#5 -13.69c
>>> Pitch(Hz(660))
E5 +1.96c
>>> Pitch(Hz(770))
G5 -31.17c
>>> Pitch(Hz(880))
A5

xenedoji is a python library I wrote to translate between notenames, cents and hertz. I use it to calculate midi pitchbend messages. It is a work in progress but you can download at the bottom of the page. Xenedoji is FLO software.

simple Hertz verses simple 12edo

simple Hz	12edo
110	A2
220	A3
330	E4  + 2c
440	A4
550	C#5 -14c
660	E5  + 2c
770	G5  -31c
880	A5
990	B5  + 4c
1100	C#6 -14c
1210	D#6 -49c
1320	E6  + 2c

Hertz	simple 12edo
110	A2
220	A3
329.63	E4
440	A4
554.37	C#5
659.26	E5
783.99	G5
880	A5
987.77	B5
1108.73	C#6
1244.51	D#6
1318.51	E6

What benefits can we find from 41edo?

41edo is the smallest edo after 12 to improve on the errors of each of the first 16 harmonics. It has enough notes to distinquish between intervals that are tuned by primes 3, 5, 7, and 11. 12edo has 2 different 3rds, one major and one minor. 41edo has 7 3rds.

12edo Harmonic Errors
2  +0.0
3  -2.0
5  +13.7
7  +31.2
11 +48.7
13 -40.5
17 -5.0
19 +2.5

41edo Harmonic Errors
2  +0.0
3  +0.5
5  -5.8
7  -3.0
11 +4.8
13 +8.3
17 +12.1
19 -4.8

41edo 3rds
vm3,  7/6,  highest prime: 7/  over
 m3, 32/27, highest prime: /3  under
^m3,  6/5,  highest prime: /5  under
~3,  11/9,  highest prime: 11/ over
vM3,  5/4,  highest prime: 5/  over
 M3, 81/64, highest prime: 3/  over
^M3,  9/7,  highest prime: /7  under

Ode to Creative Commons

A Protector of Free Information

I originally wrote this tune for Kite guitar. The score can be found for FLO and gratis here. The score and playback was made with Musescore.org. I am going to play a modified version of this source code today on Jim Snow's keyboard. This music is FLO software.

Jim Snow's Mosaichord

A Mosaichord is special because it defaults to harmonic tuning. The notes are ratios that are printed on the keys. This means that the keyboard can play the notes of the F vA C G C vE guitar open strings. The synth works by sending midi messages to an MPE compatible synth. Surge is a FLO software synth that I am using for the keyboard.

I am also developing software for the Novation Launchpad X, a 64x64 grid of pressure sensitive keys with rgb leds. I have very recently gotten the keypresses of the Mosaichord to show up on the launchpad. The launchpad is set to a full 41edo layout. Each column is the generic interval of a diatonic layout. 2nds are in the 2nd column. 3rds are in the 3rd column. Each row is 1 edostep of 41. This is how this layout supports full 41edo. For the 2nds, 3rds, 6ths, and 7ths, you can see there are 7 flavors. There are two white, blue, green, yellow, red, and the one in the middle which has no color for this layout. I have chosen to keep the one in the middle unlit because this note is the 11-limit neutral note. The neutral notes are closets to quartertones of 24edo. Since Jim's ratio synth is 7-limit, I have chosen to keep those more complex primes unlit for now. I will save primes 11, 13, 17, and 19 for when I get to violin.

Difftone Bass

How are you playing bass on a violin? Are you using a backing track?

The bass is not coming from a backing track. It comes from the violin. Two notes played together creates difference tones. These are normally much fainter that the two original tones, but amplification and distortion helps make difference tones more obvious. The bass is created from distortion, EQ, and extended JI. The more complex the ratio between two tones is, the lower the bass is. For instance if I play 5/4, the fundamental frequency between the two tones is 5 times lower than the top note and 4 times lower than the bottom note. The lowest notes I will play tonight are C and D below the E string of a standard 4-string bass. I call this technique difftone bass.

Back to Computers

Above I have described the importance of the harmonic series. I have mentioned Aristoxenus, Ptolemy, and Pythagoras. These are ancient Greek Philosophers. Though these notes are so old, and based on the harmonic series, few musicians can play them. We need tools to help us out.

There is an unsettling amount of proprietary music tools all around us. People just assume that any given music tool is proprietary. This is evident just from how many musicians are trapped in the Apple world. Musicians who don't use MacOS often instead use Windows. Now as more and more people are learning about where 12edo falls short, we are seeing more software being released for un12 tuning. Let us take a moment and ask ourselves:

We should not be trapped by non-free software tools just to experience notes that are decades, centuries, or millennia old. We do not need non-free software to experience notes that are not from Western music tradition. We do not need to give up our Human Tech Rights just to use music technology at all.

We need to know about and tell people about FLO tools.

FLO Computer Music Tools

type of gear	FLO software
laptop OS	GNU/Linux
synthesizer	Surge
distortion	Guitarix
delay/looper	SooperLooper
DAW	Ardour
score editor	musescore.org

Source Code

Here is a link to a zip of my original source code I used today. This is a work in progress and not well documented. My plan is to keep working on all my tools to make them more accessible to all, especially the average non-technical person.

License

This music is Free Software. Anyone can be free to do what they want with it as long as they are promoting freedom and not restricting the freedom of others.

FLO software is the future of democracy

Together, we can liberate technology

GNU/Linux Loves All