Sunday, 28 April 2019

Fairlight CMI IIx - Page 5 - Harmonic Amplitude Profiles

Page 5 of the Fairlight is (like page 4) about Additive Synthesis.
A Fourier analysis command allows sounds to be converted to harmonics

The above pic shows a loaded voice file. (BALDY1.VC)
This typical page 5 display shows the harmonic overtones as a set of 32 faders.
It's a bit like a graphic equaliser.
The faders are logarithmic (range is 0-255)
First load the voice by typing L,A,name<enter>

To access page 5 type

To access page 5 help type
To step through the help pages use the ADD & SUB buttons on the keyboard

Though both page 4 & 5 deal with additive synthesis and harmonics, they approach it in different ways.
Page 4 can change one harmonic over all waveform segments at once.
Page 5  can change all harmonics over one waveform segment at once.

After loading the voice you can move the faders

Notice how the waveform shape has changed from the original voice file at the very top pic.
This is after typing the command: COMPUTE

My lightpen is misbehaving but I can still get around the page using the arrow keys'
More help screen info:

If you wish to use the keyboard to set the fader type:
where n = 0 to 255
The faders are log in function.
The top of the fader = 255
Half way up the fader = 16

You can also use the ADD & SUB keys.
To zero all faders type

Setting the mode of a voice in Page 5.
This must be done in Page 3

This is a pic of page 3
Usethe arrow key to tab to MODE for the desired voice.
Type: n<set>
n = 1 or 4

Read page 4 for more info about mode 1 vs 4

tHE mode chosen in important.
A Mode 1  sound has 32 sets of faders
A Mode 4 sound will have 128.

The current segment number will be indicated on the display with a small pic of the "wave slice"
in the lower right corner.
Here is what segment 1 looks like.
Use the arrow keys to tab to "current segment" on the screen.
Type n<set>
where n = the segment number you wish to see.

You can quickly jump through segments by using the ADD and SUB keys.

Here is segment 6

Here is segment 32

Each segment is unique.
The synthesized sound changes throughout its duration.

You can compute a different waveform for each segment.
The COMPUTE command mathematically processes these to generate a waveform by additive synthesis.
The page 4 profile graph and page 5 faders are linked.
If you change one, this change will be reflected in the other.

Here is the fader page  of the voice AAATEST.VC

Here is its corresponding page 4

This is what page D looks like for AAATEST.VC

To be continued..............


Saturday, 27 April 2019

Trautonium - The birds -Peter Pichler

Thanks Peter for a wonderful performance.

This is the first time a Trautonium has left Europe.
Peter took these instruments to Perth, Canberra and Melbourne.
Sadly not Sydney. So I made a special trip to Canberra to see this.

Friday, 26 April 2019

Fairlight CMI - Page 7 - Control Parameters

This is a really important page.
Here you can modify and control various aspects of a sound.
Things like volume, looping, attack, sustain, portomento, the mode (page 4), etc..

To access page 7 type

To access page 7 help type
To step through the help pages use the ADD & SUB buttons on the keyboard  

A typical page 7 looks like this.

My lightpen is misbehaving at the moment (I'm hoping its just the graphics card), so I'm using the alpha-numeric keyboard to get around.
You use the arrow keys to move around the screen

type the numerical value you wish to enter, then hit the SET key on the lower right.

The music keyboard has 2 switches and 3 sliders (called controls):

These switches & sliders control some the parameters on the lower right of the screen.
There are in effect 6 sliders (called controls)  &  5 switches.
The other sliders & switches are controlled with footpedals that can be plugged into the rear of the keyboard.

Here is a page 2 example of a disk containing lots of voice files.

Notice that in addition to the .VC files we also have .CO files with the same names.
Eg we have a AH3.VC file along with a AH3.CO file
The .CO file is a command file. This has been linked to the voice file (using the command LINK).
So when this voice is loaded into the CMI, it will pull in its linked & specified control file.
Control files may also have different names from their intended voices.

The filter is I understand to be LP. There is one on each channel card. The cutoff frequency is raised simply by increasing the value.

Mode: see page 4 & 5.

KeyLevel: This controls the key velocity of the music keyboard. This can be patches to Level and Attack

Portamento is as you'd expect ... produces glides between each new pitch. The rate of note glide is set by the speed control.

Glissando differs from Portamento in that the glide is not continuous. Rather it's chromatic. All the notes between the start and end notes are played. If both are selected, portamento takes precedence.

Constant Time: 
This is a switch that selects between two types of glide (constant glide vs changing glide).
Constant glide /time  (on) = the same time is taken to travel any musical interval. This results in polyphonic portamento or glissando.
Constant glide /time  (off) = the rate of change is determined by SPEED. The time taken to glide varies with the size of the interval.
Attack & Damping

Attack has a range of zero to 16,384 milisecs. You can patch this to the KEYVEL to control attack time.
This works only in mode 4.

Damping has a range of zero to 65,536 milisecs
This is reduced to 16,384 in mode 4
Damping = decay time of the voice.
If loop is activated, the voice will be looped until the damping time expires

LOOP CNTRL = on, off (uses a switch - set it from your keyboard or pedals).
LOOP START =  range of 1-128.
LOOP LNGTH = length . range of 0 - 128,
The actual loop points are displayed graphically on page 4.


Thursday, 25 April 2019

Fairlight CMI IIx - Page 4 - Harmonic Profiles

Page 4 of the Fairlight is all about Additive Synthesis.
To access page 4 type

To access page 4 help type
To step through the help pages use the ADD & SUB buttons on the keyboard 

The manual introduces this page as:
 "offering facilities for rapid additive sine-wave Fourier synthesis by
harmonic amplitude manipulation."

Here is an example of a page 4 display

 Page 4 (and page 5) permit the drawing of 32 sine wave harmonic amplitude envelopes, duration envelopes, and master volume envelopes.
The harmonic envelope is similar in concept to a ADSR envelope you will find on many synthesizers.

The loop feature means that any part of the overall waveform can be made to loop (sustain).
After you draw your waveforms, the CMI will process the data and yield the final waveform by the COMPUTE command. (use either the lightpen or the alpha numeric keyboard).

Here is the first HELP sheet for page 4

There are many forms of synthesis.
Most of us are familar with subtractive synthesis where you start off with a waveform that is rich in harmonics such as a square-wave and you subtract harmonics using devices such as filters.

Additive synthesis does the reverse. You start off with the simplest building block of sound , the sine wave & you add more harmonics. In theory, you can construct any waveform using just simple sine waves.

The mathematician Joseph Fourier first proposed this theory back in the 19th century.
The concepts of additive synthesis had also existed with the invention of the organ. This instrument uses different pipes of varying pitch. These can be combined to create very complex sounds & timbres.

The harmonic series works like this:
If harmonic 1 = fundamental pitch.(FP)
Harmonic 2 = FP x 2 = harmonic 1 x 2
Harmonic 3 = FP x 3. etc etc

You need to add lots of sine-waves to produce waveforms that closely approximates idealised mathematical forms. So maybe this method isn't the best for this.
The strength of additive synthesis lies in the fact that you can exert control over every partial component of our sound. This can produce some very intricate and wonderful results.


Page 4 has 2 modes:
Mode 1 & Mode 4.
The type of sounds you want to make will help you choose which mode to use.

In Mode 1 each vertical division represents 1 waveform segment
This means there are 32 waveform segments.
Each segment in turn is sustained according to the DURATION profile position of the segment.
During this time, the amplitude is modulated according to the slope of the ENERGY profle.
It's good for doing harmonic synthesis & generating "electronic" sounds. (pages 4 & 5)

In Mode 4 each vertical division represents 4 waveform segments.
(I guess this is why its called mode 4)
This means there are 128 waveform segments.
Each segment is played once before moving to the next segment.
This is more aimed at drawing & sampling. The manual suggests it be used when making "natural sounds" .
(pages 6 & 8)

 The numbers 1 to 32 are actually lightpen switches to display all 32 waveforms. However, if this is done the display can look confusing, so its possible to hide the display of some of the waveforms (they will still remain active, and will contribute to the final sound).

To set the mode of a voice you need to use page 3.
Here is a typical page 3

Use the arrow key to tab to MODE for the desired voice.
Type: n<set>
n = 1 or 4


Wave Table Voice Facility

This option allows you to use waveforms other sine waves for additive synthesis.
Waveform segments from another loaded voice can be the source of the sound.

Harmonic numbers, now become segment numbers. You can't however select the current voice as a wave table.

In order to use this voice facility you need to load a voice into the system's memory first.
This is done in page 3.  After you have done this, you will need to select in within page 4.

To select any loaded voice for display & modification (within page 4) type:

V,filename<return>      or               V,n<return>

where filename  = the name of the loaded voice.
                      n  = the number 1-8 of a loaded voice.

The name, number, and mode of the current voice are shown in the upper right corner of the page.
The names and numbers of all loaded voices are shown on page 3 & page 7.

This page is constantly being updated as I explore the Fairlight system.
If you have a Fairlight, don't hesitate to let me know if there are any mistakes or omissions.

 To be continued...................


Pre-Raphaelites - National Gallery of Australia (NGA)

Spent some quality time at the NGA, Canberra the other day.
They had a exhibition of some wonderful art on loan from the Tate (mostly).

I remember seeing this painting as a child in a book. In the flesh it's ever more beautiful.

It's of course Ophelia by John Everett Millais.
Painted in 1851, it depicts a character from Shapesphere ... Ophelia who was driven mad after her lover Hamlet murdered her father.

Poppies signify death . Daisies innocence. The drooping branches evoke tears & sadness.

Holman Hunt - the light of the world.
Painted around 1851 - 56
It's all about salvation as Christ holding a lantern emerges from the darkness.
A later version of this toured Australia in 1905. It was seen by 4/5 of the population.

This is a cool painting about love, desire and disappointment.
It's called broken vow. Painted 1856.
The young lady in the foreground has just discovered her lover has been unfaithful.
Tales of romantic and tragic love often appear in the Pre-Raphaelites' works.
Its interesting to see how women were depicted in Victorian times.

This version of the Annunciation by Rossetti is so untraditional and very "human". Mary looks very disturbed and uncomfortable when the angel Gabriel visits.

This is a pretty famous painting ,,,, the lady of Shalott, 1888.
The subject has left the safety of her home to pursue Lancelot.

Tuesday, 23 April 2019

Monday, 22 April 2019

Fairlight IIx - Page 2 - Disk Control

Disk Control - Page 2
Page 2 is where you can view the files on the floppy disks that are used to store sounds, sequences, etc.
From here you can also load, delete, copy, rename and store files. 

The files ending in IN are instrument files.(page 3)
The files ending in VC are voice files.(page 3)

The files ending in SQ are sequencer files.(page 9)
The files ending in RS are Real Time Composer files (Page R).
The files ending in .CO are control files.(page7)

To access page 2 type 

To access page 2 help type

You can also copy files between disks.
Use the TRANSFER command. If you are using floppy disks you will need to remove the left hand disk (which contains the system disk) to copy the file to. After the copy is done, you need to replace that disk with the system disk.



Fairlight IIx - Page 1 - Index

The user interface of the Fairlight is divided into 19 pages.
They are numbered 1-9 and then A, C, D, F, I, L, N, R, S. T

When you first boot the machine this page is what you are confronted with:
It's an index or menu. The selection of other pages is its function.
You can jump to these pages using the alpha-numeric QUERTY keyboard or lightpen.

(There is one page missing from this picture ... its page T. ... the "diagnostic table"... its a means to achieve long distance diagnosis... to remotely diagnose faults.  The manual doesn't say much else about this table).

If you are using the keyboard to navigate, the first command to learn is:

P = page
n = page number or letter.

so to go to page D type

to go to page 3 type

Portabellabz BOB - 208 toolbox - Build notes

These are my build notes for the Portabellabz BOB.
Constantin's excellent expander for you easel.

These notes I'm not affiliated with Papz. These notes are purely my own personal records to help me trouble shoot if I run into any problems during the build. Hopefully these will help other DIYers.

Constantin's website is here and you can but the kits here too.
The user manual:

The BOM & official Build notes are here: