FM Zone Manual

FM Zone is an easy to use polyphonic synthesiser plugin with sophisticated FM and sample engines and a bank of flexible multi-segment envelopes to shape the sound in any direction you desire. Perfect for huge FM basses and cutting leads

The synthesiser features two powerful engines that can be layered together for a variety of complex sounds and textures. The ‘Synth’ engine features a powerful FM engine with a variety of 'special' operator types (FM, supersaw, additive, physical modelling etc) for expressive, harmonically rich timbres. The ‘Sample’ engine can be used to mix additional textures or attacks samples over the sound.

Tooltips Help System

The plugin features a built in 'Tooltips' help system. When 'Tooltips' is enabled, hovering the mouse over any control on the GUI will display a small pop-up window with a description of the function of that control. To enable tooltips select 'Show Tooltips' from the 'Settings' menu (the icon with 3 vertical lines at the top right corner of the GUI).

Controls

The plugin's knobs can be finely adjust by holding the 'Shift' key on the computer keyboard. Some knob that have a larger range of values (like 'Pitch' and 'Ratio') can be snapped to whole numbers by holding down the 'Control' key while dragging the knob. 

You can double-click (or double-tap on iOS) on the knob's label or the area just below the knob to type in exact values.

Some knobs have small triangles just to the right which will display a menu for that function, for example the Filter Resonance knob has a menu to choose the filter type. Tip: you can quickly select the next item in the menu without needing to open it by right-clicking (or control-clicking) on the triangle, or shift-click on the triangle to select the previous item.

Synth Engine

The Synth engine is based on a sophisticated 4 operator FM oscillator and a versatile 'Filter section' with 16 different filter modes.

The Synth Engine has a hidden 'Sound Editor’ (shown by clicking the pencil icon) which lets you get into the nuts and bolts of the FM algorithm (not for the faint hearted!). But in general you don't need to use the sound editor as there are over 400 preset 'Sounds' which configure all the hidden parameters of the FM engine and it's algorithms, so you can concentrate on quickly finding sounds without needing to get bogged down with the nitty gritty of FM synthesis.

Use the 'Sound Select; menu at the bottom of the Synth section to select a sound to load into the Synth Engine's FM algorithm.

Once a sound is loaded it can be broadly adjusted using the Shape, Spectrum, Timbre, Algorithm Select and Ratio knobs (see full description if these knobs below), which will modify the hidden parameters of the selected sound in various ways.

Each of the Synth engines upper row of knobs can be modulated by its own dedicated envelope, selected using the large triangle buttons above each control.

The 6 'Main' knobs of the Synth engine are:

  • Pitch: Adjusts the pitch of the Synth engine
  • Shape: Warps the output of the FM operators to add extra harmonics
  • Spectrum: Controls the amount of FM modulation in the algorithm
  • Timbre: Controls the timbre of the current algorithm
  • Filter: Sets the cutoff frequency of the synth engine's filter
  • Level: Sets the level of the Synth engine

Each ‘Main’ knob has a tweak knob below it. The 6 'Tweak' knobs of the Synth engine are:

  • Sub (sine wave icon, below Pitch): Sets the level of the Sub oscillator. Click on the small triangle to the right of the knob to select the Sub Oscillator's Mode
  • Detune (up & down arrows icon, below Shape): Detunes two layered voices for a thicker, chorus effect
  • Algorithm Select (LCD font icon, below Spectrum): Selects 1 of 20 different FM algorithms
  • Ratio (note icon, below Timbre): Increases or decreases the pitch ratio between the different operators in the algorithm, set to 1 (12 o'clock) to leave the ratios untouched
  • Resonance (graph icon, below Filter): Controls the resonance of the filter (in some filter modes this control may have an alternative function, see descriptions of the filter modes below)
  • Drive (grit icon, below FM Depth): Adds a little distortion to the FM voices for extra ‘bite'

Sample Engine

The Sample engine features a monophonic sample player with stereo detune, a dedicated 'Filter section’ and FM. 

The 3 'Main' knobs of the Sample engine are:

  • Sample Pitch: Adjusts the pitch of the Sample engine
  • Filter: Sets the cutoff frequency of the Sample engine's filter
  • Level: Sets the level of the Sample engine 

Each ‘Main’ knob has a tweak knob below it. The 3 'Tweak' knobs of the Sample engine are:

  • Detune (below Sample Pitch): Detunes two layered sample voices for a thicker, chorus effect
  • Drive (grit icon below Filter): Controls the amount of drive or resonance depending on the filter mode
  • FM Depth (exclamation mark icon, below Level): Sets the amount of FM-style modulation (modulated by the output of the Sub oscillator)

Filter Modes

The Synth engine features 16 different filter modes, the modes can be selected using the small triangle next to the filter’s tweak knob. The following modes are available:

  • 4 Pole: Basic resonant filter with internal saturation
  • Ladder: 4 Pole ladder filter based on the filter of the Mini-Moog synthesiser
  • OTA: 4 Pole filter based on the filter in the Roland Juno 106  synthesiser
  • Sallen Key: A characterful 2-pole filter similar to the filter found in the Korg MS-20
  • SEM Style: A fat filter modelled on an SEM style OTA filer
  • Clean: A clean 2-pole filter with no saturation
  • Acid: Based on the filter from the Roland TB-303
  • Bandpass 2-Pole: A 2-pole bandpass filter, Frequencies above and below the filter frequency are filtered
  • Bandpass 4-Pole: A 4-pole bandpass filter, Frequencies above and below the filter frequency are filtered
  • Highpass: Frequencies below the filter frequency are filtered
  • Vowel: A filter that simulates vocal vowel sounds, the ‘Filter’ control sets the vowel
  • Multi Notch: Steep notches are carved out of the frequency response of the sound. The resonance can be ‘excited’ to simulate a pipe or drum
  • Comb Filter: A very short tuned delay with feedback and damping, used to create a flangey, resonant effect or ‘excited’ to simulate a plucked or bowed string. In this mode  the Resonance control set's the amount of feedback
  • Crusher: Simulates the digital to analog stage of a vintage digital sampler, with lots of jitter and gritty sample rate reduction. In this mode the Filter knob sets the sample-rate and the Resonance knob set's the amount of resonance in the filtering circuit
  • Frequency Shifter: Shifts all the frequencies of the sound up by the same amount resulting in a somewhat dissonant, often bell-like sound. The Filter knob sets the cutoff frequency of the filter circuit, the Resonance knob sets the amount of frequency shifting
  • Ring Modulation: Uses a separate oscillator to modulate the level of the sound, creates harsh, harmonically rich sounds. The Filter knob sets the frequency of the modulation oscillator and the Resonance knob sets the amount of resonance of the filter circuit
  • Wavefolder: An accurate model of the Timbre section of the Buchla synthesiser. The filter shapes the sound by folding the peaks back down adding rich harmonics. The Filter knob sets the cutoff frequency of the low pass filter circuit and the Resonance knob sets amount of wavefolding 
  • Chorus: A chorus effect that can be feedback to full resonator territory, goes from subtle widening to wild dissonant clangs! The Resonance control sets the amount of feedback

 

Sub Modes

There are 14 different sub modes which can be selected by clicking on the small triangle next to the Sub knob. The first 3 modes simply select 6 different octaves for the sine wave sub oscillator.

Depending on the Sub Mode the function of 'Pitch' knob will be different, it will either control the main FM oscillator, the Sub oscillator, or both oscillators.

The modes are:

  • Sub: The sub oscillator is pitched the same the main oscillator
  • Sub - 12:  The sub oscillator is pitched an octave below the main oscillator
  • Sub - 25:  The sub oscillator is pitched two octaves below the main oscillator
  • Triangle: The sub oscillator uses a triangle waveform
  • Saw: The sub oscillator uses a sawtooth waveform
  • Square: The sub oscillator uses a square waveform
  • AM: In 'AM' mode the main oscillator is modulated using 'Amplitude Modulation' by the sub oscillator (amplitude Modulation means using the signal from once oscillator to control the volume of another). Turning the harmony knob to the right blends in some of the signal from the sub oscillator
  • Ring Modulation: In 'Ring Modulation' mode the main oscillator is modulated by multiplying its output by the output of the sub oscillator, resulting in harsh, dissonant overtones being added to the signal. Turning the harmony knob to the right blends in some of the signal from the sub oscillator
  • FM: In 'FM' mode the main synth engine oscillator is 'FMed' by the sub oscillator (FMed means the phase of the main oscillator is modulated, in the same way that classic 80s FM synths like the Yamaha DX7 do). Turning the Harmony knob to the right increase the amount of FMing and also blends in some of the signal from the harmony oscillator
  • Filter FM: In Filter FM mode the output of the sub oscillator is used to modulate the cutoff frequency of the filter, the sub knob controls the depth of the modulation. In this mode if you turn up the ‘Stereo Width’ knob it will mix in the sub oscillator and pan it to the right channel, with ‘Stereo Width’ set to zero the sub oscillator will be muted and you will only hear the main oscillator. The synth engine's ‘Pitch’ knob and envelope only affect the harmony oscillator, not the main oscillator (unlike the 'FM' and 'Fixed' harmony modes where the ‘Pitch’ knob and envelope only affect the main oscillator)
  • Vibrato: The sub oscillator is configured as an LFO (low frequency oscillator) and modulates the pitch of the synth engine to create a subtle vibrato effect
  • Noise: The sub oscillator outputs white noise
  • Noise Mod: The sub oscillator outputs white noise and uses this to modulate the pitch of the synth engine
  • Chaos: The sub oscillator outputs a 'chaotic' signal and uses this to modulate the pitch of the synth engine

Envelopes

There are 9 versatile 'multi-segment' envelopes, one for each of the plugin's main knobs. You can select the current envelope to edit using the triangular buttons above each knob. At default settings, all 9 envelopes run simultaneously at the same speed, triggered by incoming notes. A small white dot moving along the line will show the current playback position. The playback speed of the envelopes is controlled by the Speed knob.

A ‘Loop’ button is positioned at the bottom right corner of the envelope. When this button is enabled the currently displayed envelope will be looped. When loop is enabled a ‘Loop Speed’ control will appear below the button that allows you to increase or decrease the speed of the loop relative to the main envelope 'Speed' knob.

The 3 envelopes for the 'Sample' section have an extra button that appears under the ‘Loop Speed’ control when looping is enabled: 'Envelope Restarts Sample'. When this is enabled the sample is restarted whenever the envelope loops back to the beginning.

The synchronization mode for all of the looping envelopes can be set by using the menu just to the right of the 'Speed' knob (small triangle). Note: non-looping envelopes are not affected by these modes, only 'looping' envelopes will be affected. There are six available synchronization modes:

  • Off: No synchronization, loop speed is linked to the speed knob, envelopes are retriggered by MIDI notes
  • Free: Free-running envelopes (not retriggerd by MIDI notes), the loop speed is linked to the speed knob
  • Retrig: Loop speed is synchronized to the host's tempo and retriggered by MIDI notes. In this mode the loops will be exactly 1 bar long by default. There's an additional speed multiplier control for each envelope that appears under the loop button when you enable it, you can use this control to speed up or slow down individual loops. For example if you set the 'Loop Speed' control to "X2" the loop will then be twice as fast or half a bar long.
  • Locked: Loop speed is synchronized to the host's tempo and the loop's playback position is locked to the host's transport
  • Pitch: Loop speed is synchronized to the pitch of incoming MIDI notes so that the duration of the loop is equal to a singe cycle of the oscillator's waveform, great for wild audio-rate modulation!
  • Chaos: In this mode The loop position is synchronized to a random / chaotic signal

Note: in non-looping mode the playback speed of the envelope isn't linear across its path. The playback speed is faster at the start of the envelope and slows down towards its end, thus allowing you to focus on the more important transient (initial attack portion) of the sound. Enable ‘Loop’ if you require linear envelope playback speed.

There is also a presets menu for each envelope, accessed by clicking on the small triangle at the bottom left hand corner of the envelope area.

Tip: you can snap the nodes to a horizontal or vertical grid by holding down shift or control when dragging. Also holding the 'Control' key while dragging the 'Loop Speed' control will snap the values to whole numbers.

Sample Drag & Drop

You can drag a sample files onto the sample menu areas to load your own sample files. You can select the next/previous sample in a folder using the left/right arrows.

Randomization

There are 2 menu options in the 'Preset Menu' to create random variations of the current preset:

  • Randomize Preset—Completely randomizes all parameters of the current preset. The envelope nodes are not randomized
  • Mutate Preset—Adjusts all parameters of the current preset by a very small amount, subtly changing the sound in a random way

Clicking the dice icon at the top left hand corner of the GUI will repeat the last used randomization function (either 'Randomize' or 'Mutate') which is handy to quickly create variations of a sound. Note: although the envelope nodes are normally excluded from the randomization, holding down the ‘Control’ key while clicking the dice will include these, for more extreme results. Note: holding down the ‘Shift’ key while clicking the dice will always mutate the preset, no matter what the last used randomize function was. 

MIDI Learn

You can assign incoming MIDI CC (Continuous Controller) messages to any of the the instruments knobs using drag-and drop like this:

  1. Enable 'MIDI Learn' mode from the 'Settings' menu
  2. Turn a knob on your MIDI controller
  3. Drag and drop the CC number that appears in the top section of the GUI onto any of the knobs to make the assignment.

MIDI CC assignments are automatically saved for all instances of the plugin and can be reset using the 'Reset MIDI Learn' menu item in the 'Settings' menu.

Options

Click on the cog icon to show a list of different options for the current preset, the available options are:

  • MIDI Resets Oscillators: When enabled, incoming MIDI notes will cause the phase of the oscillators to reset
  • Samples Follow Pitch: When disabled, the pitch of the samples will be fixed, whatever note is played
  • Stereo Algorithms: When this is enabled algorithms that have more than 1 output will have their outputs spread left and right. Use the 'Stereo Width' knob to adjust the amount of stereo spreading
  • Legato: When enabled, and polyphony is set to 1, overlapping MIDI notes will not re-trigger the envelopes, allowing notes to glide smoothly between pitches. It can also produce interesting results in other polyphonic modes
  • Glide: Causes the notes to smoothly slide from one pitch to the next
  • Polyphony: Sets the maximum number of notes that can be played. In 'Stack 3' mode 3 voices play simultaneously for a thick, chorused sound. In 'Stack 5' mode all 5 voices play simultaneously
  • Bit Depth: Sets the bit depth of the FM Engine and Sampler's DAC (digital to audio converter)
  • Filters Follow Pitch: When enabled the cutoff frequency of the filters (of both engines) follows the pitch of the incoming MIDI notes
  • Filter Sub: Sends the 'Sub' oscillator through the filter
  • High Quality Filters: Use high quality filter algorithms. Disable this to if you want to use less CPU resources
  • Velocity To Volume: Sets how much MIDI velocity affects the volume of the sound
  • Velocity Modulation Destination: This menu allows you to choose a destination to modulate using the velocity of incoming MIDI notes
  • Velocity Depth: This knob next to the 'Velocity Modulation Destination' menu sets how much MIDI velocity affects the selected destination
  • Invert Modulation: There are small arrows next to all of the modulation 'Depth' controls, when enabled (arrow points downwards) the modulation will be applied negatively to the selected destination (decreasing rather than increasing its value)
  • Modwheel Modulation Destination: This menu allows you to choose a destination to modulate using MIDI modwheel messages (there are 2 separate slots available for modulation modulation)
  • Modwheel Depth: This knob next to the 'Modwheel Modulation Destination' menu sets how much MIDI modwheel messages affect the selected destination
  • Aftertouch Modulation Destination: This menu allows you to choose a destination to modulate using MIDI aftertouch messages
  • Aftertouch Depth: This knob next to the 'Aftertouch Modulation Destination' menu sets how much MIDI aftertouch messages affect the selected destination
  • Pitchwheel Modulation Destination: This menu allows you to choose a destination to modulate using MIDI pitchbend messages
  • Pitchwheel Depth: This knob next to the 'Pitchwheel Modulation Destination' menu sets how much MIDI pitchbend messages affect the selected destination
  • Pitchbend Range: Sets the maximum number of semitones that the pitchbend wheel can bend the notes up or down

iPad Version

The iPad version of the app is identical to the desktop version, except in how presets are handled.

On the iPad the presets are stored on a special 'sandboxed' (hidden and secure) folder that can be accessed from both the standalone version and the AUv3 plugin version. This special folder cannot be accessed by the user using the iPad's 'Files' app.

To make it easier to share and backup user presets the app will automatically backup all newly created presets into a folder that can be accessed using the 'Files' app: "On My iPad/Thump One/Exported Presets". Every time you launch the standalone version of the app it will backup any newly created presets that were created either in the AUv3 or the standalone version of the app.

Zip compressed folders of presets can be imported using the "Import Zip File...' menu item. There is also an ‘Import Zip File…’ menu item in both the sample and wavetable menus that also allows you to import folders of sample and wavetable files.

You can save your own presets using the 'Save Preset As...' menu item and typing the name of the new preset. You can save your presets into separate folders by simply typing the name of the folder and then a 'slash' character, for example typing something like "My Kicks/My Big Kick"