Synapse Audio Obsession v1.2 [WiN]

• Product: Obsession
• Publisher: Synapse Audio
• Version: 1.2.4
• Format: VST2, VST3, AAX
• Requirements: Windows 7 or later
• Source: synapse-audio.com/obsession

Synapse Audio Obsession v1.2 is a virtual analog polyphonic synthesizer emulating Oberheim OB-Xa architecture, featuring dual voltage-controlled oscillators (sawtooth, triangle, pulse with independent PWM), switchable 12dB/24dB low-pass filter with band-pass option, two ADSR envelope generators (filter and amplitude), dual LFOs with Sine/Square/Sawtooth/custom shapes and 128-step sequencing capability, comprehensive modulation matrix, two-part engine enabling Single/Dual/Split modes with 8 or 16 voices per section, per-voice parameter control (individual tuning of cutoff, attack, release, resonance per voice board), oscillator interactions (sync, cross-modulation, filter envelope modulation), Organic mode simulating hardware temperature-dependent tuning instabilities, VCA saturation mode adding harmonic enhancement, high-quality effects (reverb with shimmer, stereo delay, chorus/ensemble), MPE and NKS support, Reason Rack Extension compatibility, VST/AU/AAX formats, low CPU footprint.

Designed by Synapse Audio (Berlin-based analog modeling specialist) as “quintessential modern polysynth inspired by OB-Xa spirit but not shackled to legacy,” it balances classic analog warmth with contemporary sound design flexibility. $99 USD pricing reflects value positioning vs. competitors (€150-400 range). Target audience: analog synth enthusiasts, sound designers pursuing warmth/character, producers seeking professional-grade VA synthesis with streamlined workflow and minimal CPU overhead.

Key Takeaway

Synapse Audio Obsession v1.2 delivers Oberheim-inspired analog character at exceptional value ($99) through meticulous oscillator modeling, per-voice control unprecedented in this price tier, and innovative Organic mode adding warmth vs. static digital synths. For analog purists, warmth-seeking producers, and bass designers, it’s essential; for wavetable synthesis and broad genre flexibility, specialized competitors recommended.

Analog Warmth At Budget Pricing: When Details Matter

The Oberheim OB-Xa was legendary for one reason: warm, rich, organic polyphonic character. Not through marketing, but through meticulous oscillator design, unison detuning, and components that aged and drifted naturally.

Synapse Audio’s Obsession doesn’t try to be an OB-Xa clone. Instead, it’s focused on becoming the quintessential modern polysynth: inspired by OB-Xa philosophy but modernized without legacy constraints.

Result: Cleaner workflow, lower CPU footprint, and per-voice control Oberheim never offered.

“Very detailed, realistic emulation of an analog polyphonic synth… meticulous attention to detail modeling separate voltages and overheating components.” That’s where the magic happens—not in fancy effects or synthesis complexity, but in how meticulously the core oscillators, filter, and envelopes respond.

Bedroom Producers Blog captured the philosophy: “Doesn’t try to be. Instead, it’s solely focused on becoming the quintessential modern polysynth.”

$99 entry point reflects confidence: this is professional-grade synthesis at indie studio pricing.

Dual Oscillators: The Foundation of Warmth

Obsession’s core is two voltage-controlled oscillators (VCOs) designed to behave like real analog hardware.

Oscillator 1 — Coarse frequency tuning (0 to +3 octaves), sawtooth/triangle/pulse waveforms with independent pulse width modulation.

Oscillator 2 — Fine frequency control (0 to +63 semitones relative to Osc 1), same waveforms, independent PWM. Detuning between oscillators is the fundamental fattening control.

Why Detuning Matters: Run two oscillators at slightly different pitches = chorused, rich, warm sound. Classic unison mode technique. Real hardware detuned slightly different per voice (never perfectly synchronized). Obsession mirrors this: detuning randomizes per voice, creating organic variation, not mechanical perfection.

Oscillator Mixing: Three-state OSC 2 button (off, half volume, full volume) matches hardware design. Noise oscillator adds white noise (useful for bass thickening or sound effects).

Oscillator Interactions: Four Distinct Modulation Techniques

Oscillator Sync — When Osc 2 frequency changes while synced to Osc 1, creates classic hard sync sound (aggressive, aliased, cutting). Essential for lead sound design.

Filter Envelope Modulation (F-Env) — Osc 2 frequency modulated by filter envelope. When you sweep the filter, Osc 2 pitch follows. Creates movement: filter opens = pitch rises. Particularly powerful in combination with sync.

Oscillator Cross-Modulation (X-Mod) — Osc 1 modulates Osc 2 pitch (analog FM effect, but between oscillators only, not affecting filter). Creates bell tones, metallic character, extreme timbral variation.

Unison Mode with Detuning — Multiple voices, each slightly detuned. Results in lush, fat, floating character. Users report: “Incredibly fat basses.”

The Filter: Warm, Musical, Oberheim Character

Single low-pass filter with band-pass option. Oberheim-flavored (warm, musical curve, not surgical).

Slope Modes:

• 12 dB per octave (gentler, smoother character)
• 24 dB per octave (4-pole, steeper, more aggressive resonance response)

Controls:

• Cutoff Frequency (primary resonance control)
• Resonance (feedback, can self-oscillate for pad foundations)
• Envelope Amount (controls filter envelope depth, ±6 range)

Keyboard Tracking: Filter follows keyboard pitch (can be disabled or fine-tuned). Standard analog synth feature.

The Organic Mode: Analog Imperfection, Digitally Simulated

This is where Obsession diverges from perfectionistic design.

Real analog synthesizers don’t hold pitch perfectly. Components age, temperature fluctuates, voltages drift. Each voice slightly different, never synchronized.

Obsession’s “Organic” knob simulates this: randomly modulates all voice parameters subtly (oscillator pitch wobbles, filter frequency fluctuates, envelope times vary per voice).

Effect is randomized per voice, not a synchronized LFO. Result: subtle, organic, warm. Eliminates robotic digital perfection.

User testimonial: “Makes it sound really organic… not a constant LFO, just sort of up and down down and up a bit up a bit down a bit.”

Difference is audible and emotionally significant. With Organic off = pristine, static. With Organic on = alive, breathing, warm.

Per-Voice Parameter Control: Unprecedented Detail

Classic hardware synthesis problem: all voices identical (boring, robotic). Solution in hardware: each voice board has hand-matched components (expensive, desirable, vintage).

Obsession’s innovation: each voice board (8 or 16 available) has individual trimpots:

• Cutoff Frequency trim (each voice’s filter slightly different pitch)
• Attack/Release time trims (envelope slightly different per voice)
• Oscillator scaling, filter scaling (voice-specific response curves)

Practical result: each voice is slightly different, creating natural variation, richer texture, less robotic character.

“Picking out the parameters that matter, stops you getting too in-depth obsessed by tiniest details”—intentional design philosophy.

The LFO Steps Feature: Beyond Standard Modulation

Two LFOs (standard sine, square, sawtooth waveforms). Nothing revolutionary there.

But LFO Steps mode enables custom sequencing: up to 128 steps per LFO, free-hand drawing of custom shapes, tempo sync. Results in rhythmic, evolving modulation patterns (not just periodic LFO waves).

Use cases:

• Rhythmic bass modulation (step-sequenced filter opening on beat)
• Evolving pad texture (custom shape that changes over 8 beats)
• One-shot envelopes (draw custom envelope, trigger with LFO rate)

Advantage over traditional LFOs: programmatic control over modulation evolution, not just rate/depth knobs.

Modulation Matrix: 6-Slot Comprehensive Routing

Generous modulation matrix enables:

• Multiple LFO targets simultaneously
• Envelope modulation of parameters beyond standard (oscillator pitch, resonance, etc.)
• Complex chains (LFO modulates filter, while envelope modulates oscillator)

6-slot capacity described as “generous” (vs. premium synths with 12+ slots, but still professional-grade).

Architecture: Sources (Filter Envelope, Amp Envelope, LFO 1/2, MIDI) route to Destinations (Oscillator frequencies, pulse widths, filter cutoff/resonance, envelope parameters). Amount knobs enable positive/negative modulation.

Reverb: Exceptional Quality + Shimmer Innovation

Coded by Mirko Ruta (premium reverb designer), reverb lifts Obsession beyond basic effects tier.

Standard Reverb:

• Room simulation with tail control
• Wet/dry balance
• Warm, lush character

Unique Feature: Shimmer Mode
Blends reverberated signal with octave-transposed copy. Regen knob feeds transposed signal back into reverb for additional octaves. Results in ethereal, pad-friendly effect.

User assessment: “Pleasant-sounding shimmer, somewhat shrill on occasion.”

Caveat: Not premium-tier shimmer reverbs (Valhalla), but excellent for the price bracket. Reverb inclusion alone justifies $99 price point.

Delay & Chorus: Useful Supporting Effects

Delay: Stereo delay with tempo sync. Straightforward, effective. Single delay (not dual for ultra-wide stereo, but adequate for most use cases).

Chorus/Ensemble: Lush ensemble thickening effect. Classic character, useful but not innovative. “Quite useful” user assessment.

Two-Part Engine: Dual Synth Sections + Split Mode

Modes:

• Single: One monophonic voice
• Dual: Two synth sections layered
• Split: Two sections on separate keyboard regions (left/right split)

Voices: 8 or 16 per section (16-voice or 32-voice total)

Use case example: Dual mode enables pad + lead simultaneously (different filter settings, envelope shapes, effects). Split mode enables bass on left, lead on right.

Professional depth without overwhelming interface.

Sound Character: Warm, Rich, Organic, Versatile

Bass: “Incredibly fat” — unison mode with detuning, resonant filter, enables thick, warm, chorused bass. Users report excessive reliance (using “TOO MUCH” on bass tracks).

Pads: “Lush, airy, floating” — reverb shimmer + ensemble + Organic mode create ethereal, warm character. Filter envelope modulation adds movement.

Leads: “Crystal clear, articulate” — tight filter control, responsive modulation enable precise melodic definition.

Overall Philosophy: Analog warmth without digital artifacts. Responsive oscillators (vs. static wavetable synths), humanized by Organic mode fluctuations.

Workflow: Simple Outside, Deep Inside

Front Panel: Clean, intuitive layout. All primary controls visible (oscillators, filter, envelopes, LFOs). Hardware panel aesthetic (knobs, switches). Colors code sections (blue modulation, brown oscillators).

Back Panel: Modulation matrix, LFO Steps, effects, voice adjustment. Organized, not overwhelming.

Philosophy: “Simple on the outside, deceptively deep when digging into voice tuning and step LFOs.”

Accessibility: Not beginner-friendly (analog synthesis concepts steep), but intermediate+ producers find intuitive, streamlined.

CPU Footprint: “Surprisingly minimal” — low resource overhead vs. comprehensive competitors.

Pros & Cons

Pros	Cons
Exceptional $99 price point (vs. €150-400 competitors).	Single delay (not dual for stereo width).
Per-voice control unprecedented in price tier.	6-slot modulation matrix (adequate, not extensive).
Organic mode adds warmth vs. static digital synths.	Shimmer reverb good, not premium tier.
Low CPU footprint (minimal system overhead).	Oscillator cross-mod with oscillators only (not filter).
Clean workflow (essential parameters, avoids rabbit holes).	Analog synthesis steep learning curve for beginners.
Warm, responsive oscillators (not static wavetable).	Preset library “not for everyone” (taste-dependent).
LFO Steps enables rhythmic, custom modulation.	Relatively new (vs. established U-He, Arturia).
Excellent reverb quality with shimmer innovation.	Two-part engine adds complexity (not always needed).
MPE and NKS support (modern controller integration).	Not suited for wavetable/FM purists.
Professional sound quality (user consensus: “ultimate VA synths”).	Single oscillator envelope modulation point (F-Env only).

Where Obsession Stands

vs. Arturia Oberheim OB-X8:

• Obsession: Focused design, lower price ($99), cleaner UI
• Arturia: More comprehensive effects, additional synth engines, higher price (€199+)
• Verdict: Obsession streamlined quality, Arturia comprehensive versatility

vs. U-He Repro:

• Obsession: Newer, modern Organic mode, lower entry price
• U-He: Established reputation, deeper modulation, comparable price (€79-89)
• Verdict: U-He historical credibility, Obsession contemporary innovation. Both equally praised.

vs. Massive X, Pigments:

• Obsession: Analog emulation focus (not wavetable/FM/granular)
• Competitors: Broader synthesis types, higher versatility, complex UI, higher price
• Verdict: Different philosophies. Obsession = analog purist, others = comprehensive workstations.

FAQs

Final Verdict

Synapse Audio Obsession v1.2 proves that analog warmth doesn’t require premium pricing: meticulous oscillator modeling, per-voice control unprecedented in this bracket, and innovative Organic mode = professional-grade virtual analog synthesis at $99.

Two VCOs with sync, cross-modulation, and filter envelope modulation enable classic analog interactions. Dual ADSR envelopes, LFO Steps sequencing, and modulation matrix provide sophisticated modulation without overwhelming interface.

Per-voice parameter tuning (cutoff, attack, release, scaling) creates natural variation, humanizing every voice. Organic mode adds temperature fluctuation simulation, eliminating robotic perfection.

Reverb quality exceptional (Mirko Ruta coding), shimmer effect innovative. Delay and chorus supporting but adequate. Effects inclusion elevates $99 value proposition dramatically.

Not ideal for wavetable synthesis purists, extreme modulation complexity, or broad genre versatility. But for analog enthusiasts, warmth-seeking producers, bass designers, and educators, it’s uncompromising specialized excellence.

Rating: 4.6 / 5

Virtual analog polyphonic synthesizer with dual VCOs, switchable 12dB/24dB filter, two ADSR envelopes, dual LFOs with 128-step sequencing, modulation matrix, per-voice parameter tuning, Organic mode (analog temperature fluctuation simulation), reverb with shimmer, stereo delay, chorus. Two-part engine: Single/Dual/Split modes, 8 or 16 voices. VST/AU/AAX, Reason Rack Extension. MPE and NKS support. Low CPU footprint. Warm, organic sound character. $99 USD. Exceptional value. Essential for analog purists and warmth-seeking producers; supplementary for wavetable/FM specialists.