Thor Polysonic Synthesizer in Propellerhead Reason 4.0

The Thor Polysonic Synthesizer (which would be called “Thor” later for convenience in this article) is a new-introduced device in Propellerhead Reason 4. The following passages would explain what it does by dividing it into different parts, and then describe how each part coordinates with other parts and external devices. This article supposes that the reader has the basic idea of general settings/buttons of Reason.

The controller panel

• Pitch bend & Range setting
• Modulation Wheel
• Keyboard Modes:

  Mono Legato vs. Mono Retrigger

  whether a new “attack” of the envelope is triggered

  Polyphony & Release Polyphony

  The later sets how many released notes are not cut even there are new note-on.

  Portamento setting

  when to do portamento, “auto” means “only when the previous note is still held”

• Trigger setting – It sets what inputs would trigger the note/oscillators.
• Rotaries and Buttons – would be covered later…
• Master Volume – only for outputs 1 & 2 (though Thor may have 4-channel outputs)

Voice & Global sections

This part is just like routed basic synthesizers. 3 oscillators are mixed into 2 different filters and then mixed again. The twice-mixed audio then is modified by different envelopes and filters. Though Thor has some advanced usage for much more complicated routings.
Something important to note in the voice sections (left half part):

• Each oscillators and filters could be different types by clicking the arrow pop-up in the upper left corner.
• In fact, Filter 2 could have 4 inputs: 3 oscillators and the audio from the shaper.
• The mixer does not “mix” the audio inputs from the 3 oscillators, it just modifies their amplitude. You should turn on the routing (by lighting up the numbered-button at the left side of the filters) to feed needed oscillators’ signals to filters.

Knobs for oscillators

• OCT, SEMI, TUNE: units for them are octaves, semitones and cents, respectively. By using these knobs, we can assign different pitches for different oscillators even by pressing only one key.
• KBD: stands for “keyboard track”, not only an on/off setting. For instance, by setting it as 64 and pressing E3, we’ll get a D3 frequency.
• Others depend on oscillator type.

Knobs for filters

• Drive: modifying the input level, would be silence if set to zero
• FREQ and RES: frequency and resonance.
• ENV: the level of the filter effect modified by “Filter Env” (below the “Amp” part)
• INV: decides whether to invert the envelope, just like the button in SubTractor.
• VEL: decides how much the velocity would affect the envelope level. (Note the difference between velocity and volume)

Other details

• The knob “KBD FOLLOW” in LFO1 works like keyboard tracking.
• The output of Shaper would not be zero by setting its drive zero.
• After panning in the Amp part, the audio signals are treated as stereo.
• Some settings may change other settings. For example, with KBD set nonzero, a filter’s FREQ value would not be constant anymore.
• You can do AM on OSC1 and OSC2.
• The level of synchronization of OSC1 to OSC2 and OSC3 could be assigned. (BW stands for “bandwidth”) This means that OSC1 may affect the frequency of the other two.

Modulation Bus Routing Section

This section is another feature of Thor and could be divided into 3 small parts. Let’s start with the easiest left half part by examples.

• The 1st line of the section means that the audio signal of LFO1 would affect the pitch of OSC2 by level 15.
• The 4th line means that Rotary1 (which is in the controller panel) would affect Freq of Fiter3 in its opposite way.
• The 5th line means that the amount of modulation would also depend on the value of Rotary2.

The 2 parts in the right half part are both based on the basic part. The 1st line in the right half part means that wheeling up the modulation wheel would cause the decrement of “Filt1 Freq” and increment of “Filt1 Res”; the lower right part, in short, allows us to modulate a destination by 3 sources.

Other details

• The button “CLR” would clear the settings of its line. (Just try!)
• “Audio Input” of 3 filters and Amp could be assigned as destination. The assigned input would NOT clear the original input, that is, we can route audio signals from other external devices to Thor’s filters.
• On the other hand, if a filter has no input from the voice section, the filter may still have output.
• CV and Audio signals could be routed to each other.
• To the right of the button in Controller Panel there’s a spin set for a pitch. If set, pressing that key would NOT trigger a note-on, but momentarily turn on the button’s modulation. Note that it works only for un-lit button.

Step Sequencer

Well, this section could be said independent from the Thor device. You don’t have to understand the niggling routing settings to use this part. This section is like a simplified Matrix Pattern Sequencer. You can specify each step’s pitch, velocity, gate length, duration … etc. The main differences you may note are that in Thor:

• To make the notes pronounced, you should turn on the “STEP SEQ” in Trigger part of Controller panel.
• There are only 16 steps available, but you can use less than 16 if you wish. (By screwing the STEPS knob in the lower right or clicking the red circle) Turn off the pink rectangle light would cause that step to be mute.
• There are no pattern banks or shuffle function.
• You can use non-synced rate on step running.

And then let’s check other settings…

Run mode and direction

Repeat

The sequencer would not stop after pressing RUN button.

1 Shot

The sequencer would run the whole step once.

Step

The sequencer runs only one step by each RUN pressing.

Pendulum 1

1, 2, 3, …, 15, 16, 16, 15, 14, …, 3, 2, 1, 1, 2, 3, …

Pendulum 2

1, 2, 3, …, 15, 16, 15, 14, 13, …, 3, 2, 1, 2, 3, …

Edit knob

The current value of the edit knob means what kind value the step knobs are showing.

• Note: Octave range could be set (the center is C3).
• Velocity: Note that the velocity does NOT mean volume exactly.
• Gate length: measured in percentage.
• Step duration: the unit is what you set in sequencer rate.
• Curve 1 & 2: only used for bus routing section

Other details

• You can use some functions in “Edit” menu, like “Random Sequencer Pattern.”
• RESET button would reset everything on Step Sequencer, even those values not editing.

PDF download

Reference: Propellerhead Reason 4.0 Operation Manual