SJ-2 Version 1.
1 Contents Contents Getting Started Introduction.................................................................3 Installation...................................................................4 Adjusting Parameters...................................................4 Programming the SJ-2 Oscillators.....................................................................6 PWM.............................................................................9 Filter..................................................
3 Getting Started 2 Please note that if you are new to synthesis, parts of this user guide may appear to be ‘a bit heavy’. Don’t worry, once you start turning knobs and flicking switches on the SJ-2, it will all start to make sense. Introduction Congratulations on acquiring the Manx SJ-2 synthesizer. We hope you will find the rich, organic sound of the instrument to be as satisfying as we do.
4 Getting Started
6 Programming -Oscillators 2 1 1 1 1 1 Oscillator Overview When playing a guitar, the sound produced originates from the strings. In the case of a synthesizer, the basic sound comes from a section called the ’oscillator section’. Just as a guitar can have twelve strings instead of six, so a synthesizer may feature two oscillators instead of one.
7 Programming -Oscillators OSCILLATOR SYNCHRONIZATION (2) Normally, the two oscillators are free running (simulated); they operate independently. This means that when you press a key multiple times, the resulting sound may not be exactly the same each time, because the oscillators will interact with each other differently each time.
8 Programming -Oscillators 4 4 5 5 OSCILLATOR CROSS MODULATION (4) Yet another factor which can affect the pitch of oscillator 2 is the output from oscillator 1; that is oscillator 1’s waveform - when at the top of its cycle osc 2’s pitch will rise and when at the bottom of its cycle, osc 2’s pitch will fall. Clearly this pitch fluctuation will be very fast indeed and will serve to provide a timbrel effect rather than discernible pitch variance.
9 Programming -PWM Pulse Width Modulation Both of the SJ-2’s oscillators have the option of selecting a pulse wave, which looks like this: The pulse waves have a feature which none of the other waveforms have; The peak to trough ratio can be adjusted. We do this using a parameter known as ‘pulse width’. Pulse Width Pulse Width increased This is a superb feature for two reasons: Firstly, one wave shape - pulse - becomes an infinite number of wave shapes; all pulse waves with different pulse widths.
10 Programming -PWM Pulse width & pulse width modulation are so important that the SJ-2 has a section dedicated to them: The controls labelled ‘PW’ set the pulse width for each oscillator. If the oscillator is set to any wave other than pulse wave, the settings here will have no effect. The actual Pulse width can be made to fluctuate around the point set by the ‘PW’ slider, by an amount set by the ‘PWM’ slider - this stands for ‘pulse width modulation’.
11 Programming -Filter Meet the SJ-2’s Filter 1 2 3 4 5 6 7 8 As mentioned in the introduction, considerable effort has gone into giving the SJ’s low pass filter that extra bit of ‘flare’ one normally associates with analog technology. However, from a user’s perspective, the filter controls are the same as you would find on any other subtractive synthesizer - if you’re familiar with synthesis, you won’t need to spend a long time reading this section.
12 Programming -Filter 1 2 3 4 5 6 7 8 CUT-OFF FREQUENCY (2) RESONANCE (3) REZ - sets the cut-off frequency of the filter. - sets the resonance of the filter. CAUTION: Turning up the resonance can lead to a profound increase in sound volume, perhaps unexpectedly. Please consider both your speakers and your ears and use this feature cautiously. ENVELOPE SOURCE (4) - determines whether the filter cut-off is modulated by envelope 1 or envelope 2.
13 Programming -Envelopes Meet the SJ-2’s envelopes The SJ-2 has two ADSR type envelopes, which can be scaled by velocity and key-tracking Envelopes are triggered when a key is depressed; from this point the output of the envelope (used for modulation) will develop over time in a predictable profile, defined by the user, using controls in the envelope section.
14 Programming -Envelopes The SJ-2 has two envelopes, both triggered simultaneously by depressing a key. The output of these envelopes can be assigned to various parts of the synth; pitch, volume, filter cut-off, cross-modulation and more. Envelope 1 to Pitch Envelope 1 to oscillator cross modulation Envelope 1 to Pulse Width Switchable: Envelope 1 or Envelope 2 to Filter cut-off.
15 Programming -Envelopes 8 Key follow: These sliders affect the intensity of the envelope generators according to how high up the keyboard a particular key is pressed. High settings will cause higher keys to follow a more intense envelope profile. Self-Compensating Sustain Level CAUTION: If you reduce the SJ-2 envelope’s SUSTAIN amount, the peak of the envelope’s output can actually rise - the SJ-2 attempts to recover overall volume level .
16 Programming -Envelopes SHORT ATTACK TIMES At extreme settings, the peak of an SJ-2 envelope can be so snappy that it becomes important to co-ordinate the attack times of the two envelopes, in order to prevent the filter from peaking after the volume has decayed to sub-optimal levels. This is really only an issue when you have some moderate attack time on the filter envelope, zero attack on the volume envelope but a swift decay on the latter.
17 Programming -LFO / OSc Mix Low Frequency Oscillator LFO Destinations Just like the SJ-2’s main oscillators, the low frequency oscillator (LFO) creates waveforms. You can select from four different wave-shapes; sine, triangle, square and random. Unlike, the main oscillators, the LFO is not influenced by which key has been depressed; the frequency is controlled by the slider labeled ‘RATE’ in the LFO 1 section and it can go down to sub-audible frequencies.
19 Control Panel The SJ-2 control panel provides all the input you need to effectively control the synthesizer. Here, you will find master volume and master tune knobs, facilities to load and save patches, polyphony assignment, a second LFO and a basic arpeggiator. Please note that apart from the patch memory menus, all controls in this section save with the patch, including Master-Tune and Test-Tone controls. PROGRAMMER Patch menus: Click on the white button labelled ’Patch ‘ in order to select a patch.
20 Control Panel UNISON MODE The SJ-2 can play a maximum of 6 notes at the same time. Use the switch in the Unison mode section to layer multiple notes under each key. Here is a breakdown of the possible settings: Poly - The SJ-2 is in its normal polyphonic mode (6 voices). Solo - The SJ-2 acts like a monophonic synthesizer. Two - The SJ-2 becomes 3 note polyphonic and two voices are stacked for each note played, these two voices will be detuned in accordance with the Unison Detune knob.
21 Midi Learn / Zoom Continuous Control & Midi Learn Right click on any switch or knob to bring up a menu which will allow you to either manually assign a continuous controller number or use the Midi Learn facility: Simply click midi learn and then adjust the control on your midi control keyboard which you would like to associate with the SJ-2 parameter. When you save your song the continuous controller assignments will be saved and will be functional when you reopen it later.
23 Appendix One - Audio filters Appendix One: The basics....... You may think of a synthesizer filter as being rather like a single ‘tone’ control that you might find on a home audio system such as a personal CD player.
24 Appendix One - Audio filters Frequency and Waveforms...................a little bit of magic! 8 It just so happens that sound waves don’t like to propagate through air in any form other than a sine wave. It stands to reason; air which is of a higher pressure because of a sound wave will want to expand quickly, but this urgency will dampen off as the pressure returns to normal, and a subsequent rebound in the other direction will complete a sign wave pattern.
25 Appendix One - Audio filters If we add yet another sine wave, higher pitched and quieter than the others, we get this: + = As you can see a regular waveform which is not a sine wave begins to emerge. It turns out that when many different sine waves are added together, the resulting wave-shape can be anything at all. In complex cases such as speech, you are still hearing a ‘chorus’ of sine waves, but in this case, the relative volumes and pitches of those wave would be constantly changing.
26 Appendix Two - Troubleshooting Appendix Two TROUBLESHOOTING & KNOWN ISSUES These issues apply to SJ-2 version 1.3 and may be resolved in subsequent versions. Defaulting to Patch 1, upon start-up: With some VST host programs, when you reopen a song which contains an instance of the SJ-2, for some reason the host software tells the SJ-2 to default to the first patch.
27 Appendix Three - Information for users Appendix Three- Information for users CREDITS We would like to thank the following contributors: Jeff McClintock. David Haupt, Daz Disley, Rob Herder, Rick Jelliffe, Christian-W. Budde & Chris Kerry, who have provided code used in Manx synthesizers.
3D Anaglyph representation of the Manx SJ-2 Synthesizer.
Other Manx Instruments: Thanks for going with the SJ-2! Bit 100 v2 MM-2 XS-4 Destiny v2 Gigmate v2 http://www.manxsynthesizers.
