Acustica Audio intros EXPANSE-5: your modern take on a 5-voice legend.

Expanse-5 (XP-5) is a deeply expressive virtual analog synthesizer born from Acustica’s groundbreaking MAREA series. Available in VST3, AU, and AAX formats, XP-5 faithfully captures the soul of a legendary, five-voice polysynth of the late analog era—celebrated for its rich tone, musical flexibility, and iconic presence in countless recordings.

Faithful to the principles of classic subtractive synthesis, XP-5 captures the essence of that era while pushing the boundaries with modern enhancements. From an oversampled, high-resolution architecture to advanced modulation and spatial features, XP-5 blends vintage character with cutting-edge digital precision—offering a timeless sound redesigned for today's creative workflows.

At its core lies MUST (Modular Unified Synthesis Technology), Acustica’s proprietary engine designed to deliver ultra-low latency, efficient CPU usage, and pristine audio quality. This cutting-edge architecture ensures that XP-5 delivers not just authenticity, but also the reliability and flexibility demanded by today's music producers and sound designers.

The Legacy Reimagined

XP-5 is more than just a digital re-creation—it's a tribute to a synthesizer that shaped the sound of countless award-winning albums across genres. This instrument, often considered the pinnacle of analog polysynth design, was beloved for its lush textures, intuitive layout, and ability to inspire. XP-5 encapsulates this heritage, offering the same expansive tonal range and luxurious analog character, now enhanced with modern digital control and refinement.

Originally conceived with five voices—one for each finger of a performing hand—the instrument's unique architecture promoted expressive polyphonic play. XP-5 retains this spirit but pushes beyond the limitations of the original, offering enhanced stereo capabilities and expanded voice count. This allows for richer, wider, and more immersive soundscapes.

Advanced Digital Architecture: Oversampling Without Compromise

Expanse-5 (XP-5) is not just another digital emulation. It represents a breakthrough in synthesizer architecture—engineered from the ground up to run entirely at oversample rate, without reliance on block-based processing. Every module—from oscillators to filters, envelopes, LFOs, and performance controls—operates continuously at elevated internal frequencies, ensuring unmatched temporal precision and audio fidelity. The result is a seamless synthesis environment where modulation, signal shaping, and sound generation happen sample-by-sample, in real time.

Why Oversample Everything?

Running the entire signal chain at oversample rate delivers tangible sonic benefits:

• Extreme detail and transients, ideal for sharp percussive sounds and fast envelopes.

• Clean modulation and PWM, free of stepping, zipper noise, or aliasing.

• Consistent phase behavior, crucial for stereo imaging and analog-style motion.

This architecture allows XP-5 to preserve the sonic integrity of its analog inspiration while offering far greater resolution and responsiveness. This minimizes aliasing, enhances transient clarity, and enables smooth, analog-like modulation across the entire signal chain.

Expanse5 | Launch video

Key Features

• MUST-Powered Engine

Hybrid synthesis core combining convolution and analog-style modeling.

• Full Oversampled Architecture

Entire signal path runs at high internal rates—no block processing, resulting in cleaner sound, smoother modulation, and minimal aliasing.

• Scalable Polyphony

Polyphony ranges from 2 to 10 voices, starting with 5 by default—just like the original. Superstereo takes it further by expanding the voice field for a wider, fuller sound.

• Dual Oscillators

With cross-mod, sync, PWM, noise, and fine detune.

• Multimode Filters & VCA

Classic subtractive behavior with envelope, key follow, and velocity control.

• Superstereo & Age

Adds stereo depth and analog imperfection with adjustable drift.

• Advanced Modulation

Fast envelopes, audio-rate LFOs, and intuitive routing.

• Studio-Grade Effects

Includes chorus, delay, reverb, EQ, and a powerful multiband saturator.

• Performance Toolkit

Real-time MIDI learn, portamento, arpeggiator, and visual feedback.

• 450+ Pro Presets

Curated by sound designers, producers, and musicians.

Tone Calibration & Authenticity

After building the core engine of XP-5, the team focused on the challenging task of calibration—ensuring the sound was not just technically accurate, but emotionally authentic. A carefully modeled Rev 3 unit served as the main tonal reference, with input from trusted experts and extensive beta testing driving further refinements. To deepen the process, a rare Rev 2 was also examined to capture subtle differences in tone and behavior.

That said, even two Rev 3s from the same production period, with nearly identical serial numbers, can sound noticeably different. The condition of each unit, component aging, and years of use all shape its voice. No two analog synths ever sound exactly alike, which is why our goal wasn’t to build a generic emulation—but to capture the living personality of our hardware. Not just its frequency curves, but its soul.

Beyond Original

While XP-5 faithfully captures the essence of its analog predecessor, it goes further by introducing performance-enhancing features, such as:

• Age: Simulates analog wear with drift and imperfections for vintage warmth.

• Superstereo: Expands the stereo image by intelligently duplicating and modulating each voice with complete pitch and phase decorrelation, creating a deep, immersive three-dimensional soundstage.

• Sub: Adds a dedicated sub-voice for focused, controllable low-end presence.

• Advanced Effects: Built-in high-quality effects (saturation, chorus, delay, reverb) derived from renowed Acustica Audio plugins.

• Multiband Dynamics: Integrated compression inspired by OTT for punch and cohesion.

XP-5 GUI

About the technology

XP-5 is powered by a revolutionary technology known as Modular Unified Synthesis Technology (MUST).

MUST is a hybrid synthesis technology that integrates the precision of analog circuit behavior modeling with Acustica Audio’s signature convolution-based approach. It incorporates advanced features such as nonlinear convolution, dynamic Volterra series, and time-varying models to faithfully reproduce the complexities and nuances of analog hardware.

This innovative combination delivers exceptional sound quality and unmatched realism, providing cutting-edge functionality and dynamic responsiveness. With its state-of-the-art design, MUST establishes a new standard in virtual instrument synthesis, seamlessly blending the authenticity of vintage sound with the versatility and performance demands of modern music production.

Marea: Acustica's virtual instrument series

The Marea line by Acustica Audio heralds a transformative era in virtual instruments, embodying the fluidity and dynamism of the ocean's currents. Just as the tide—"marea" in Italian—moves with natural elegance and power, this series is designed to seamlessly connect creativity and innovation in music production.

This innovative combination delivers exceptional sound quality and unmatched realism, providing cutting-edge functionality and dynamic responsiveness. With its state-of-the-art design, MUST establishes a new standard in virtual instrument synthesis, seamlessly blending the authenticity of vintage sound with the versatility and performance demands of modern music production.

Technical information:

• Supported formats: VST3, AAX, and AU.

• Compatible with Windows 10 and 11.

• Compatible with macOS 10.15 (Catalina) to macOS Sonoma (version 14.x).

• Intel, AMD, and ARM compatible.

• Native Apple Silicon support (Rosetta not supported).

Price and availability

Expanse5 introductory price: €99 |41% OFF until July 14, 2025 at 11:59 pm CET (reg. price €169)

Get it here!

The product is at an introductory period for the first four weeks after release or until the first official version is released; this implies that the product may receive improvements, changes, or fixes available through Aquarius Desktop updates.

Try our FREE 30-Day Trial

Please remember that trials expire 30 days after authorization, and we strongly recommend not using trial products in commercial sessions or any important project.

Expanse5 user's manual

XP-5 webpage: https://www.acustica-audio.com/shop/products/EXPANSE5

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