What Is a Pitch Raise and When Does a Piano Need One?

You call a piano tuner. They arrive, play a few notes, shake their head slightly, and say: “This piano needs a pitch raise before I can tune it.”

If you’ve never heard that term before, it sounds ominous — and maybe expensive. But a pitch raise is actually a common, straightforward procedure. Understanding what it is, why pianos need it, and how it works will help you make better decisions about your piano’s care.

What Is a Pitch Raise?

A pitch raise is a rough, preliminary tuning pass that brings a piano up to (or near) standard pitch — usually A440 (the note A above middle C vibrating at 440 Hz) — before a fine tuning can be done.

It’s not a substitute for tuning. It’s a preparation for tuning.

Here’s why it’s necessary: when a piano has dropped significantly below standard pitch, you can’t simply tune it note by note in the normal way. The reason comes down to physics — specifically, string tension and the structure of the piano itself.

Why You Can’t Just Tune a Badly Flat Piano Normally

A piano has over 200 strings. Each one exerts tension on the soundboard and the plate (the cast iron frame). The total string tension in a full-size grand piano can exceed 20 tons.

All of this tension is balanced. When all the strings are in their normal tuned state, the structure is in equilibrium.

But when a piano has been sitting unplayed for years, or kept in a fluctuating environment, the strings go slack and the tension decreases. The soundboard and plate subtly shift. The whole instrument settles into a lower-tension equilibrium.

Now here’s the problem: if you tune each note up to pitch one at a time, starting from bass and moving to treble, by the time you’ve finished the treble, the bass notes you tuned first will have gone flat again — because raising the treble tension shifted the structure slightly. You’d be chasing a moving target.

A pitch raise solves this by roughing in the tension first, bringing all the strings close to pitch in a single quick pass, without trying to be precise. Once the piano has settled into its new equilibrium, a proper fine tuning can be done.

What Is Standard Pitch?

A440 is the international standard: the note A above middle C vibrates at 440 cycles per second (Hz). All modern piano tuning is referenced against this standard.

Before the 20th century, pitch standards varied widely by country and era — some orchestras tuned to A435, others to A452. Today, A440 is universal.

A piano that’s at A440 can play in tune with other instruments — guitars, orchestras, electronic keyboards, recordings. A piano that’s significantly below pitch sounds fine by itself, but it won’t work in ensemble settings.

How Far Below Pitch Is Too Far?

There’s no hard rule, but common thresholds:

Up to 5 cents flat: A skilled tuner may be able to fine-tune in one pass, though results may not hold as well.
5–30 cents flat: A pitch raise is typically recommended before fine tuning.
30–100+ cents flat: Multiple pitch raises may be needed, spaced over several sessions.

One cent is 1/100th of a semitone. A piano 50 cents flat sounds noticeably off, and its strings are carrying significantly less tension than they should.

What a Pitch Raise Actually Looks Like

The tuner works through the piano quickly — far faster than a normal tuning — bringing each string close to pitch without trying to achieve precision. The goal is rough elevation, not accuracy.

This pass puts stress on the strings, pins, and structure. After the pass, the tuner pauses to let the instrument settle, then begins the careful fine tuning from scratch.

In some cases, a piano is so far below pitch that the tuner will recommend two or more pitch raise sessions, spaced weeks apart, before attempting a final fine tuning. This is especially true for old or fragile instruments where sudden tension increases carry some risk of string breakage.

How Often Does a Piano Need a Pitch Raise?

Most well-maintained pianos that are tuned twice per year will never need a pitch raise. Regular tuning keeps the string tension close to standard, and small adjustments don’t require a rough pass first.

A pitch raise is typically needed when:

The piano hasn’t been tuned in more than 2–3 years
The piano was stored in a damp or unheated space
The piano was moved and then left untuned
The piano was purchased secondhand in unknown condition
The instrument is old and has a history of neglect

Does a Pitch Raise Hurt the Piano?

The short answer: a well-executed pitch raise is safe for most pianos. Strings are designed to be tuned, and raising pitch is a normal part of maintenance.

That said, there are some considerations:

Old strings: Strings that are very old, corroded, or already weakened have a higher chance of breaking during a pitch raise. An experienced tuner will assess the string condition before proceeding.

String breakage: Strings can break during pitch raises. This is relatively rare on modern instruments but more common on older pianos. A broken string requires replacement — not a crisis, but an additional expense.

Multiple passes: If the piano is severely flat, rushing it up to pitch in one aggressive pass is riskier than taking two or three sessions. A good tuner will recommend the conservative approach.

Why Does Pitch Drift Happen?

Several factors cause pianos to lose pitch over time:

Humidity changes: Wood swells and contracts with humidity fluctuations. The soundboard — which pushes up against the strings — changes shape with the seasons, affecting tension.

Neglect: Strings slowly stretch over time, especially in the first years after a piano is strung. Without regular tuning, they drift.

Environmental extremes: Pianos kept in basements, garages, or near heating vents are exposed to more extreme humidity and temperature swings, causing faster pitch drift.

Age: Older pianos with worn tuning pins may not hold pitch as well. The pin grips less securely in the pinblock, and the string slips after tuning.

What to Expect After a Pitch Raise

Here’s a realistic timeline:

Session 1: Pitch raise + fine tuning. The piano sounds much better, but may not hold pitch perfectly because the strings are still settling.
A few weeks later: A follow-up tuning. Now the strings have stabilized at the new tension level and the piano holds much better.
Ongoing: Twice-yearly tuning keeps the piano at pitch indefinitely.

If a piano has been neglected for many years, expect the first few sessions to involve more work before the instrument settles into a stable routine.

How This Connects to Learning to Tune

For aspiring piano technicians, understanding pitch raises is important because:

It reveals the instrument’s structure — you can’t grasp pitch raises without understanding how string tension, the soundboard, and the plate interact.
It teaches tuning sequence — pitch raises require efficient, fast work. Learning to do one teaches you how to move through the piano quickly.
It’s part of every service call — a professional tuner encounters pianos needing pitch raises regularly. It’s not an exotic procedure; it’s a standard skill.

In 88 Lessons, we cover pitch raises in context — explaining the physics, the technique, and the decision-making process that a professional uses when assessing a new piano.

The Takeaway

A pitch raise is not a problem — it’s a normal maintenance procedure for pianos that have drifted below standard pitch. It prepares the instrument for accurate fine tuning by roughing in tension across all the strings at once.

If your tuner recommends one, it means they’re doing their job properly. And if you’re learning to tune, understanding why it’s necessary is one of those insights that makes you a better technician.

Want to Learn More?

88 Lessons is a free daily podcast for anyone who wants to learn to tune a piano by ear. We cover everything from the physics of sound to the practical skills of a working piano technician — one 15-minute lesson at a time.

Start with Lesson 1 today.