🎧 Shiori Kujo's Research Journal Vol.01: The "Logic" Behind Perception

The other day, Rin enthusiastically wrote about one of our experiments at the lab.

Today, I’d like to revisit the same experiment from a slightly different perspective.

If we’re going to follow in the Boss’s footsteps, intuition alone isn’t enough.

Understanding why something works is just as important as discovering that it works.

1. The Brain Measures Space Through Familiar Sounds

Rin excitedly described the moment she suddenly “saw the room” after adding the sound of a hair dryer.

While her reaction was genuine, the phenomenon itself has a well-established explanation in psychoacoustics.

Humans struggle to estimate the size and shape of a space when listening only to diffuse sounds such as rainfall. These sounds lack clear spatial references.

However, introducing a familiar everyday sound, such as a hair dryer, changes everything.

Because the brain already knows how that sound should normally behave, it immediately begins comparing the direct sound with the reflected sound. From those subtle differences, it unconsciously estimates the dimensions of the surrounding environment.

What appears almost effortless in Tommy’s dearVR PRO 2 workflow is actually the result of decades of accumulated experience.

Every parameter reflects a deep understanding of how the human brain constructs a sense of space, an understanding refined through more than three decades of professional post-production work.

2. Creating Spatial Layers with Scene Rebalance

I’d also like to expand on our experiment using iZotope RX12 Scene Rebalance.

Rin described it as separating the voices from the crowd and suddenly making the space “come alive.”

She wasn’t wrong.

However, from a technical standpoint, what we were really manipulating were distance cues.

By separating foreground voices from background ambience and assigning different reflection characteristics to each layer, the brain receives far clearer information about depth.

Rather than hearing one large mass of sound, it begins organizing the scene into multiple spatial layers.

This layered structure forms one of the fundamental principles behind the immersive sound field MASTERSOUND aims to create.

Looking at the Boss’s Pro Tools sessions often reminds me of studying the blueprints of a carefully engineered building. Every sound has a purpose, a position, and a relationship with every other sound. 🎧

3. The Uncharted Territory of Vertical Localization

There is one area that still fascinates us the most.

Vertical localization.

Rin jokingly described it as “absolute hell.”

To be honest…

I don’t entirely disagree.

Reproducing sounds above or below the listener through headphones is extraordinarily difficult.

Unlike horizontal localization, vertical perception depends heavily on the complex interaction between the outer ear, head, shoulders, and even the listener’s own body.

This makes vertical positioning one of the least understood and most challenging areas of binaural audio production.

However, Tommy is already looking beyond conventional approaches.

Rather than relying solely on plugin presets, our research focuses on understanding how the human brain constructs spatial perception itself.

Perhaps the answer is not simply creating more accurate virtual acoustics.

Perhaps it is learning how to communicate with the brain more effectively.

Every experiment at MASTERSOUND raises new questions.

For us, that is not a sign of failure.

It is evidence that we are getting closer to understanding how humans truly perceive space.

And personally…

I find that far more exciting than simply finding the “correct” answer. 🌿