The One Interval That Unlocks Aural Piano Tuning
The One Interval That Unlocks Aural Piano Tuning
88 Lessons Newsletter — Issue #1
Welcome to the first edition of the 88 Lessons newsletter. Every week, I’ll share one focused insight from the curriculum — something you can hear, practice, and build on. No filler, no fluff. Just the kind of knowledge that a master piano technician would normally spend years transmitting to an apprentice.
Let’s start with the interval that changes everything.
The Octave Is Not Your Friend (Yet)
Most people assume that if you can hear an octave — two notes where one sounds exactly “twice” the other — you’re ready to tune a piano. And they’re half right.
The octave is the foundation of piano tuning. But it’s also the most deceptive interval on the instrument. A perfectly tuned octave on a piano sounds slightly different from a mathematically pure octave. Why? Because of inharmonicity — the physics of steel piano strings causes their overtones to stretch slightly sharp of where pure math predicts. A tuner who chases mathematical perfection ends up with a piano that sounds wrong to every human ear in the room.
Here’s the shift that unlocks everything: stop listening for the note, and start listening for the relationship between notes. Specifically, start listening for beating — the subtle wavering pulse you hear when two frequencies are slightly out of alignment. Learning to hear beats, count them, and control them is the core skill of aural piano tuning. And the interval that teaches this skill most clearly, most reliably, to absolute beginners?
The unison.
Why the Unison Is the Perfect Teacher
A unison — two strings tuned to the exact same pitch — is the clearest demonstration of beating you’ll ever hear. When those two strings are slightly misaligned, you hear a throbbing, wavering sound. As you tune one string toward the other, the beating slows. When it disappears completely, the strings are in perfect agreement. Clean. Stable. Musical.
This is the first thing professional tuners learn to control, and it’s exactly where Lesson 1 of the 88 Lessons curriculum begins. The unison is unambiguous. There’s no theoretical complexity — just physics, your ears, and the string. Once you can reliably zero out a unison beat, your ears have learned the most important thing they’ll ever learn about piano tuning.
The octave comes next. Then the fifth. Then the temperament octave. But all of it builds on this.
🎧 Try This Today: The Unison Listening Exercise
You don’t need a piano to start training your ears right now. Here’s a simple exercise:
Step 1: Open a free tone generator app or website (search “online dual tone generator”). Set both tones to 440 Hz (A4).
Step 2: Listen. The two tones should blend into one clean, steady sound — no wavering, no pulse.
Step 3: Slowly raise one tone by 1–2 Hz (to 441 or 442). Listen carefully. You should begin to hear a slow pulse — a gentle throb in the sound. That pulse is the beat. Count how many times it pulses per second.
Step 4: Raise it a bit more (to 444–448 Hz). The pulse speeds up. The further apart the frequencies, the faster the beat. This is the fundamental physics of piano tuning in your hands.
Step 5: Bring it back to 440 Hz. The beat disappears. That moment — when the pulse dissolves into stillness — is what piano tuners call “locking in” the string. Remember that feeling. That is your destination every time you touch a piano.
Do this exercise for 10 minutes. You’re not just listening. You’re training your auditory cortex to perceive micro-differences in frequency. This is the ear training that takes most people years to develop by accident — but it can be developed deliberately, starting today.
Listen: The Latest Episode of 88 Lessons
In this week’s episode, we go deeper on the physics of beating and why the piano is tuned to stretch rather than pure mathematical intervals. You’ll hear the difference between equal temperament and pure tuning — and understand why every great tuner plays by ear, not by numbers.
🎙️ Listen to the latest episode at 88Lessons.com
Until next week — keep your ears open.
Eathan Janney Piano Technician | PhD Neuroscience | Founder, 88 Lessons
P.S. Next week: Why your phone’s tuning app is lying to you — and the one thing it can’t tell you that your ears always can. Don’t miss it.
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