Why A440 Matters: Tuning Your Piano to Standard Pitch

Most of the time, I recommend tuning a piano to A440 (the modern North American standard for pitch). Even if the piano is significantly flat and requires a major pitch raise, tuning to A440 is usually the goal. But like anything, there are a few consequences to be aware of.

Isn’t That Hard on the Piano?

Yes… and no.

Tuning a piano, whether it’s flat or not, always carries some risk. One of the most obvious is string breakage. Piano strings are under high tension, and because they curve around metal pins and over wooden contact points, friction can build up along their length. If that friction doesn’t release and/or the string is already weak, it may snap… sometimes even when the pitch is being lowered. While strings are more likely to break during a big pitch raise, breakage can happen any time they’re adjusted.

There’s also the cast iron plate to consider. In extremely rare cases, it can crack as the tension of the strings is increased. If it does, it sounds like a cannon going off. I’ve been doing major pitch raises on a weekly basis for over a decade, and I’ve never had this happen. Other techs I know say it’s only happened once or twice in their careers. Technicians who do more rebuilding work may have seen it 10 times or so in a lifetime. It’s possible, but quite rare.

Why Not Just Tune It Flat?

Tuning a piano below A440 might seem like a safe shortcut, but it can cause issues, especially if you’re using the piano with other instruments or for training the ear.

Here are a few things that can go wrong:

• If you play other instruments with the piano, it will sound noticeably “off” unless the other instruments are tuned down to match. It’s not always easy or possible to tune a stringed or wind instrument this low.

• If you’re using the piano as a pitch reference for singing, you won’t be singing accurate pitches.

• If a child has perfect pitch, tuning the piano flat can affect how they hone or label their internal sense of pitch over time.

When I Recommend Tuning Below A440

There are a couple of cases where I do recommend tuning the piano flat:

• If I’m unsure the piano can handle a pitch raise. Some older pianos or instruments in fragile condition might not withstand the stress. In these cases, I play it safe, tune it flat, and revisit the pitch raise at a future date after I've seen how the piano responded.

• If the piano’s use makes it unnecessary. If it isn’t being used with other instruments, isn’t used for pitch reference in vocal practice, and the client is only playing for personal enjoyment, tuning below standard pitch can be completely valid.

Screenshot of TuneLab Piano Tuner app

FAQs About Pitch Raises

• What happens if you skip a pitch raise?

  You don’t really “skip” one… it’s either needed or not. If you choose not to do it, the piano remains flat until you decide to address it later.

• Can an old piano be tuned to concert pitch?

  It depends on the condition of the instrument. Some older pianos can handle the tension, while others may not. The best way to know is to ask your technician.

• Will tuning my piano break the strings?

  It’s definitely possible, though it’s not unfixable. Strings are under high tension, and weak spots or friction points can cause one to snap, especially during a big pitch raise. Tenor and treble strings can be replaced on the spot. Bass strings have to be special ordered.

• What’s the difference between a regular tuning and a pitch raise?

  A regular tuning makes fine adjustments when the piano is already close to A440. A pitch raise is for pianos that are far below pitch and need a larger change in string tension. Because of this, they’re less stable at first and will drift out of tune more quickly.

• What’s the difference between concert pitch, standard pitch, and A440?

  Concert pitch refers to the tuning reference for a group of instruments in performance, which has varied over time. Today, the ISO defines international standard pitch as A440, meaning the A above middle C vibrates at 440 Hz.