Page 4 of the Fairlight is all about Additive Synthesis.
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
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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.
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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
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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 strengths of additive synthesis lie in the fact that we can exert control over every partial component of our sound, which can produce some very intricate and wonderful results.
Page 4 has 2 modes:
Mode 1 & Mode 4.
In Mode 1 each vertical division represents 1 waveform segment
This means there are 32 waveform segments
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.
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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)
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To be continued...................
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.
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 strengths of additive synthesis lie in the fact that we can exert control over every partial component of our sound, which can produce some very intricate and wonderful results.
Page 4 has 2 modes:
Mode 1 & Mode 4.
In Mode 1 each vertical division represents 1 waveform segment
This means there are 32 waveform segments
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.
--------------------------------
To be continued...................