Synesthesia in the Mastering Room

I have a form of synesthesia called chromesthesia. When I hear sound, my brain produces an involuntary visual response. Colors, shapes, sometimes movement. Not metaphorically, and not as a way of describing how music feels. It just happens, automatically, the same way another person might recognize a face.

I've had it for most of my life. For a long time I assumed everyone did. It wasn't until much later that I learned there was a name for it and that I wasn't the only mastering engineer who experiences it. I know two other mastering engineers with synesthesia. It's a strange thing to explain if you've never experienced it, so I thought it might be worth describing what it actually looks like from my listening position.

What Chromesthesia Actually Is

Synesthesia is a neurological phenomenon where stimulation of one sense automatically triggers a response in another. There are many forms of synesthesia. Some people see letters or numbers as colors. Some associate specific tastes or smells with shapes. Chromesthesia, sometimes called sound-to-color synesthesia, is the auditory variety.

I didn't have a name for it until my lovely wife gifted me a copy of Musicophilia by Oliver Sacks. If you haven't read it, Sacks was a neurologist who spent his career documenting the strange and fascinating ways music intersects with the human brain. Reading it was one of those moments where a book just quietly explains your entire life back to you. Oh. So this is a thing. This thing has a name. Other people have it too.

It's not a choice, and it's not something I consciously turn on or can turn off. A snare hit might arrive as a sharp burst of orange squares moving sideways, depending on the reverb tail or roominess. A sustained middle register note on a piano might be deep dark blue and slowly drifting outward depending on the decay. Bright and aggressive high frequencies tend to show up as white or pale yellow, almost transparent acute triangles. A warm, well-saturated low end is often a dense and heavy amber or brown.

It doesn't look the same every time for every person with chromesthesia, either. These are my colors, my shapes, my movements. Someone else with the same chromesthesia might have an entirely different visual vocabulary for the same sounds. It's personal, fairly consistent for me, and involuntary. It's just part of how I'm wired.

What a Mix Actually Looks Like

When a mix lands on my desk, the first thing I do is listen. No hands on anything, no notes yet. Just the record. The visual response starts immediately, running in the background while I'm still forming my first impressions of what the mix needs.

A mix with excess low-mid buildup, that common muddiness around 200-400Hz that clouds the body and clarity of a record, tends to look brown and compressed. Congested, like a room with too much furniture. A mix with too much high-frequency energy is bright and yellow and sharp, almost too intense to look at. Over-saturated and harsh. Fatiguing visually before it's fatiguing audibly.

Recently, a mix came in that immediately looked claustrophobic in the low mids. I couldn't initially identify why. I went back to the low end and focused on the relationship between the kick and bass guitar. The bass guitar was sitting a little too much on top of the kick, and the two needed their own space. A narrow EQ cut on the full mix, right where the bass was crowding the kick, gave each of them room, and the relationship opened up.

That's the kind of thing I'm talking about. The visual response doesn't tell me what EQ move to make. It just gives me a place to look.

A well-balanced mix has space in it. The colors and objects are distinct and not fighting each other. There's clear movement and depth. I can see the elements of the arrangement occupying different visual space, even if I couldn't describe exactly where each one sits.

Over-limited mixes are immediately obvious. They look flat. Static. Boxy. Two-dimensional. Like a photograph with no contrast. The dynamic range, or lack of it, has a visual quality that's hard to miss once you've seen it enough times.

None of this replaces what I see on a spectrum analyzer, meter, or what I hear through my monitors, most importantly. But it runs parallel to it, constantly, whether I want it to or not.

Does This Mean I Trust What I See Over What I Hear?

No. Full stop.

Chromesthesia doesn't replace listening. It doesn't replace calibrated monitoring, an accurate room, reference tracks, measurement tools, or the technical foundation that mastering is built on. I'm not looking at a mix and making EQ decisions based on what color I see. That would be bananas.

What it adds is another perceptual cue running alongside the analytical one. I'm not using it as a second measurement system, and I don't think of it as one. When something feels off in a mix and I'm not immediately sure what it is, the visual response can sometimes give me a starting point or a direction to investigate. It's not always faster, and it's not always right. But it is another piece of information available to me, and that can be useful.

There's a parallel here with the way a mix engineer can hear a problem and start moving toward it before they've consciously identified exactly what it is. That's pattern recognition built from years of focused listening. For me, chromesthesia can sometimes do something similar: it can point my attention toward something before I've consciously named the problem.

What It’s Like When a Record Really Lands

Most sessions are methodical. You listen, you analyze, you adjust, you listen more, you make decisions. The chromesthesia is there but unremarkable, just part of the background.

And then, every so often, a record comes in and the experience is breathtaking.

Some mixes produce a visual response that's almost cinematic. The colors are deep and distinct. Movement corresponds to the dynamics and arrangement in a way that feels coherent and intentional. Everything seems to occupy its own space. There's a kind of visual clarity to the record that is difficult to describe without making it sound more mystical than it is.

Those are the records I remember. They stay with me after I leave the desk.

That doesn't change what I do to the record. Those records get the same process as everything else. But it does change what it's like to work on them. After more than two decades of doing this, I've spent a lot of time listening closely to records. I'm not going to pretend that the experience of genuinely connecting with one doesn't matter.

Why I’m Telling You This

If you've worked with me, you may have heard me describe a mix as brown, boxy, or claustrophobic. That isn't shorthand or studio poetry. It's a fairly literal report of what I'm seeing, and now you know where it comes from.

I also think it's worth being open about how engineers listen. Everyone doing this work at a high level has their own internal process, built from years of focused listening, and most of it never gets talked about. This is part of mine.

That's all this is: another way my brain responds to sound while I'm doing the same job I've always done.