The Science Behind Anthem Room Correction (ARC®)

This page explains how Anthem Room Correction (ARC®), developed with Dr. Peter Schuck, uses advanced algorithms, multi-point measurements, and psychoacoustic principles to deliver precise, natural, and lifelike sound in any room. It covers the evolution from early ARC versions to ARC Genesis, highlighting how digital filters, minimum-phase correction, and frequency-domain processing optimize speakers and subwoofers for real-world listening environments. Readers learn why multiple measurements, intelligent equalization, and modern digital processing make ARC the industry-leading solution for high-performance audio.

The Science Behind Anthem Room Correction (ARC®)

Dr. Peter Schuck, Ph.D., takes you behind the science of Anthem Room Correction (ARC®)  — exploring the engineering, advanced mathematics, and acoustic principles that power the world’s most effective room correction system.

How Have the ARC Genesis Algorithms Improved?

Since its debut in 2010, the Anthem Room Correction (ARC®) algorithm has continuously evolved — shaped by years of customer feedback, real-world data, and advances in computing power. The result is a new generation of ARC Genesis that can precisely adapt to a broader range of speakers, rooms, and configurations than ever before.

But the algorithm is only part of the story. Anthem’s engineers have also refined how ARC determines the optimal equalization and bass management settings for your system. Digital filter design is a complex, non-linear process — there’s no single “perfect” answer. ARC Genesis intelligently evaluates thousands of possible solutions, analyzing crossover points, slopes, and target responses to deliver correction curves uniquely optimized for your space and equipment.

The outcome? Smarter algorithms, sharper precision, and sound that’s unmistakably Anthem.

Why Does ARC Require Multiple Measurements?

Sound behaves differently throughout a room — frequency response can vary dramatically from one spot to another. If a room correction system uses data from only a single location, it might improve performance in that one precise spot but degrade it everywhere else. In fact, optimizing for one ear could even make things worse for the other.

Anthem Room Correction (ARC®) takes a smarter approach. By capturing multiple measurements across your listening area, it builds a detailed acoustic map of your room. These measurements reveal how sound interacts with your walls, furniture, and layout, allowing ARC to create correction filters that enhance the overall performance — not just at one “sweet spot,” but throughout the entire listening area.

Because great sound shouldn’t require keeping your head in a vice.

What is psychoacoustics, and how does it relate to room correction?

Psychoacoustics is the study of how humans perceive sound. Anthem’s proprietary algorithms leverage this science to ensure your system sounds natural and engaging. Our ears and brains expect to hear sound behave a certain way in a room — forcing a speaker to measure perfectly flat can actually make it sound unnatural. ARC understands this relationship between speakers and room acoustics, applying intelligent correction that smooths unwanted peaks and dips while preserving the room’s natural character — allowing you to fully immerse yourself in the experience.

What Are Time-Domain and Impulse Response, and How Do They Relate to Room Correction?

Time-domain refers to the strength of a signal over time. In room correction, it’s used to describe a loudspeaker’s acoustic output — its impulse response — measured at a specific point in the room. ARC plays short tone sweeps, capturing the impulse response of each speaker to understand how sound behaves in your space.

However, time-domain data alone doesn’t tell the full story. Frequency-domain analysis is far more powerful for room correction — in fact, major audio formats like DTS and Dolby rely on frequency-domain processing.

Once Anthem Room Correction (ARC®) captures a speaker’s impulse response, it converts that data to the frequency domain using a Fast Fourier Transform (FFT). This creates a detailed model of the speaker’s frequency response. ARC then calculates custom equalization filters, applying smoothing and averaging to deliver an ideal in-room frequency response — precise, balanced, and tuned to your unique listening environment.

What Is Mixed-Phase Room Correction, and Why Doesn’t ARC Use It?

Sound from a loudspeaker to a microphone is inherently mixed-phase. Some room correction systems attempt to address this by treating the speaker as a combination of a minimum-phase system and an all-pass system. While correcting a minimum-phase system is straightforward, equalizing an all-pass system requires time delays, which must be limited to avoid imprecision. This limitation can produce pre-ringing — a backward echo that blurs transients — and is especially noticeable at low frequencies, where time delays are longer. Human ears are highly sensitive to these artifacts, which can degrade the listening experience.

Mixed-phase systems also struggle when working with multiple measurement points, which are needed to cover an entire listening area. At low frequencies, it’s difficult to find matching phase across measurements, limiting the available correction points. In practice, this can prevent precise correction at problem frequencies, forcing adjustments at nearby points instead of exactly where they’re needed.

ARC avoids these limitations by using frequency-domain room correction. This approach allows Anthem Room Correction (ARC®) to select precise crossover points to correct peaks and dips in a speaker’s frequency response, delivering accurate, artifact-free results without the compromises or risks associated with mixed-phase equalization.

Why Are Minimum-Phase Filters Ideal for Room Correction?

Minimum-phase filters respond quickly, with just a brief, natural decay — similar to the sound of a drumstick striking a drum: a sharp, immediate impact followed by a short, fading resonance. This fast, natural behavior mirrors how most real-world sounds occur. Because minimum-phase filters replicate this natural impulse response, they are perfectly suited for room correction, delivering accurate, lifelike sound without introducing unwanted artifacts.

How does typical analog or digital equalization alter phase relationships?

All filters that change a loudspeaker's frequency response also change the speaker's phase response. Typical analog and digital filters are minimum phase filters (i.e., filters that have only a small effect on the phase) and change the phase response in such a way that has a particular and unique relationship to the frequency response.

Why Is Digital Room Correction Superior to Analog?

Analog filters rely on passive components like resistors and capacitors to shape frequency response. Even high-quality components have tolerances — resistors can vary by 1%, capacitors by up to 5%. While that may sound small, these variances make it difficult to hit precise correction points or craft complex, high-order filters needed for accurate room correction.

Analog filters are also impractical for real-world room correction. Each room has a unique acoustic signature, meaning analog equalization would need to be hand-built for every space, a costly and cumbersome process. Parametric and graphic equalizers offer some flexibility, but they still lack the precision and control required to truly optimize a room’s sound.

In the digital domain, filters are created with extreme precision — 16-, 24-, 32-bit (or higher) processing allows exactly shaped filters at exact frequencies. This precision makes digital room correction the only practical and effective solution for achieving accurate, lifelike sound in any room.