Sequential Trigon 6 Polyphonic Synthesizer

Sequential present the Trigon-6 six-voice analogue polyphonic synthesiser, designed by the Sequential team and the last design that Dave Smith contributed to.
 
The Trigon-6 features the same form factor, UI, and ease of use as Sequential’s acclaimed Prophet-6 and OB-6, but adds a new twist: a 3-VCO-plus-ladder filter sound engine for a voice that is both bold and familiar. It’s a sound that has proven its appeal since the dawn of the synth era.

The VCOs and VCFs are new discrete designs that deliver maximum analog punch and presence. Sequential has put its own unique stamp on this timeless sound by adding feedback, drive, and a new 2-pole mode to the ladder filter for more versatility and a broader tonal palette.

Here's what Sequential have to say

The Trigon-6 is Sequential’s polyphonic take on the classic, thick and creamy, 3-oscillator-plus-ladder-filter analog sound that defined the dawn of the synth era. It’s a sound that bridges genres and styles — now refined and redefined with Sequential’s own modern imprint. 

All-New Filter and Oscillator Design

At the heart of the Trigon-6 sound are three newly designed voltage-controlled oscillators (with triangle, saw, and pulse waves) and an enhanced version of the ladder filter that Sequential created for its Pro 3 mono synth. The switchable 2/4 pole resonant filter design has dedicated drive and feedback controls that make it effortless to go from bold and crunchy to silky and smooth with a simple knob turn. 

The Perfect Package

The Trigon-6 has all of the best qualities of Sequential’s acclaimed Prophet-6 and OB-6 synths — 6-voice polyphony, unrivaled playability, easy programmability, and modest footprint — packed into a four-octave, semi-weighted keyboard with velocity and channel aftertouch. What differentiates it from its siblings is its unmistakable “3-oscillators-through-a ladder-filter” punch. It raises the bar for what the ideal power poly can and should be.

Rounding Out The Picture

Naturally, the Trigon-6 has the full complement of Sequential’s ”must-have” sound-sculpting features including super snappy envelopes, a syncable LFO with multiple waveforms and destinations, a polyphonic step sequencer, and an arpeggiator. Best of all, the knob-per-function front panel of the Trigon-6 puts these conttrols at your fingertips. And the ready-made palette of 500 factory and 500 user presets provides classic basses, leads, and pads to jump start any project.  

More Power Features

Also present is Sequential’s classic Poly Mod, with enhancements for creative sound design. Modulation sources are filter envelope and oscillator 3 (both with bi-polar control). Destinations include oscillator 1, 2, and 3 frequency, oscillator 1, 2, and 3 pulse width, filter cutoff, and feedback. Unison mode is here as well, featuring configurable voice count (1-6 voices for up to 18 simultaneous oscillators) and key modes. 

Dual Effects

The dual effects section provides studio-quality reverbs, delays (standard and BBD), chorus, flanger, phaser, and ring modulator. The independent stereo distortion effect adds on-demand aggression and is 100% analog.

Adjustable Vintage Character

Finally, to give even more classic organic warmth to an already classic synth, there’s the Vintage Knob, which adds voice-to-voice variations in calibration and component behavior. Vintage behavior is adjustable from subtle to extreme to emulate the stability of a perfect modern instrument or a time-worn relic. 

More Than the Sum of Its Parts

Add all of this up and the Trigon-6 represents a modern synth workhorse with a bold, versatile, 3-oscillator ladder filter-based sound. It builds on the past, refines the present, and redefines the future for accessibility, portability, and playability in an analog poly synth.

Technical Specifications 

Oscillators

• Three discrete VCOs per voice
• Simultaneously selectable wave shapes:
  • triangle
  • sawtooth
  • reverse sawtooth
  • variable-width pulse
• Pulse width per oscillator
• Hard sync: oscillator 1 syncs to oscillator 2
• Low frequency mode (oscillator 3)
• Keyboard tracking on/off (oscillator 3)
• Oscillator feedback and drive controls for increased signal saturation 
• White Noise source
• Keyboard pitch tracking on/off

Low-Pass Filter

• Switchable two/four-pole, discrete, resonant, low-pass, ladder filter per voice
• Filter can be driven into self-oscillation with the Resonance control
• Bi-polar filter envelope amount
• Velocity modulation of envelope amount
• Keyboard tracking: off, half, full

Filter Envelope

• Four-stage (ADSR) envelope generator
• Velocity modulation of envelope amount

Amplifier Envelope

• Four-stage (ADSR) envelope generator
• Velocity modulation of envelope amount

Low Frequency Oscillator

• Five wave shapes:
  • sine
  • sawtooth
  • reverse sawtooth
  • square
  • random (sample and hold)
• LFO sync 
• Initial amount
• Mod destinations:
  • oscillator 1 frequency
  • oscillator 2 frequency
  • oscillator 3 frequency
  • oscillator 1 pulse width
  • oscillator 2 pulse width
  • oscillator 3 pulse width
  • filter cutoff, amp (VCA)

Poly Mod

• Sources: oscillator 3 (bi-polar) and filter envelope (bi-polar) 
• Destinations:
  • oscillator 1 frequency
  • oscillator 2 frequency
  • oscillator 3 frequency
  • oscillator 1 pulse width
  • oscillator 2 pulse width
  • filter cutoff
  • feedback amount

Vintage Knob

• Recreates vintage synth characteristics by adding voice-to voice variations in component behavior 

Aftertouch

• Source: channel (mono) aftertouch with bi-polar amount
• Destinations:
  • oscillator 1 frequency
  • oscillator 2 frequency
  • oscillator 3 frequency
  • LFO amount
  • amplifier envelope amount
  • filter envelope amount
  • FX mix A
  • FX mix B

Clock

• Master clock with tap tempo
• BPM control and display
• MIDI clock sync

Arpeggiator

• Selectable note value: 16th note, 8th note triplet, 8th note, dotted 8th note, quarter note
• One, two, or three octave range
• Up, down, up/down, random, and assign modes

Sequencer

• Polyphonic step sequencer with up to 64 steps and rests

Effects

• Stereo analog distortion
• Dual, 24-bit, 48 kHz digital effects, including:
  • reverb (room, hall, plate, spring)
  • delay (full bandwidth digital delay and emulated bucket brigade)
  • chorus
  • flanger
  • phase shifter
  • ring modulator
• Delay sync
• True bypass maintains fully analog signal path when digital effects are off

Performance Controls

• Full-sized, semi-weighted, 4-octave keyboard with velocity and aftertouch
• Backlit pitch and mod wheels
• Spring-loaded pitch wheel with selectable range per program (1 to 12 semitones up and down)
• Transpose controls for an 8-octave range
• Hold switch latches held notes on
• Polyphonic portamento
• Unison (monophonic) mode with configurable voice count, from one to all six voices, chord memory, and key modes
• Preset switch: when on, the front panel is live — what you see is what you hear

Patch Memory

• 500 user and 500 factory programs in 10 banks of 100 programs each
• Direct program access, including single-button access to the current set of 10 programs

In/Out

• Left/mono and right audio outputs (2 x 1/4” phone jack)
• Headphone output (stereo, 1/4” phone jack)
• MIDI in, out, and thru ports
• USB for bidirectional MIDI communication
• Filter cutoff expression pedal input
• Volume expression pedal input
• Sustain footswitch input
• Sequencer start/stop footswitch input

Power

• IEC AC power inlet for internal power supply
• Operates worldwide on voltages between 100 and 240 volts at 50 to 60 Hz; 30 watts maximum power consumption

Physical Specifications

• 31.8” L x 12.7” W x 4.6″ H (80.7 cm x 32.3 cm x 11.7 cm)
• 20 lbs (9.5 kg)