PART 1: OUT-OF-TUNE ACOUSTIC PIANOS ARE USELESS
Most notes on a piano are linked to two or three strings that struck simultaneously with the hammer associated with the note’s key. These multi-string notes are called unisons.
Each string of a unison is normally tuned to match the pitch or vibration rate of the others. If this is the case, the tone will be beautiful, clear and undistorted. In addition, the loudness of the unison note can be changed to subtle degrees, producing the important musical effect called dynamics. In addition, the tone of a properly tuned unison note can also be subtly varied.
Control of these factors, in combination, represent the essence of piano artistry.
As soon as one or more strings of the unison note fall out of tune to a significant degree:
A. The tone changes from beautiful to ugly and annoying. In short, musical sound is replaced with distortion, like a stacticky radio station.
B. In comparison to neighboring notes that are in-tune, an out-of-tune unison is usually considerably and inappropriately louder. For a student who has learned to control the volume of a series of neighboring notes, they will experience the frustration of repeatedly trying to restrain the previously learned force of particular finger so the volume out-of-tune unison blends with the others. In the worst cases, this will be impossible.
Once numerous unisons across the keyboard are out of tune, it’s impossible to produce anything with the piano that can be rightfully considered music. Instead, it becomes a noisemaker with keys attached.
In such cases, there can be no meaningful enjoyment of the music, which discourages the student from practicing.
In addition, individual notes can be out of tune with other ones (to be referred to as intonation).
Regularly listening to a piano with bad unisons and intonation does untold damage to a student’s developing musical ear.
Regarding bad unison, the student is unable to practice the volume and tone control skills being taught in their lessons.
Regarding bad intonation, they are not hearing standard pitches or note combinations as they practice. It’s somewhat like learning to paint pictures with sunglasses on, i.e. the “colors” of musical sound are distorted.
In sum, allowing a student to practice on an out-of-tune piano is setting them up for musical failure.
Doing so also represents a false economy: saving money on tunings leads to wasting much more money on lessons that are ultimately unproductive.
To use a sports analogy, practicing on an improperly maintained piano is like giving a child a warped wooden racquet to use for their tennis lessons.
PART 2: WHY PIANOS GO OUT OF TUNE
Piano strings, made of metal, appear to be very rigid. Nonetheless, they need to be flexible enough to vibrate and produce audible sounds. As a result of this flexibility, their tension (tightness) is essentially changing constantly–starting when your piano technician packs up their tools and walks out the door.
Beyond that, the large wooden soundboard of a piano, and two long wooden strips called bridges, glued together, support the downward pressure of the strings.
As the humidity surrounding the piano changes (a near constant phenomenon), the soundboard/bridge assembly rises (with higher humidity) or falls (with lower humidity). This changes the tension on the strings in a random fashion, which causes the piano to produce jangling/noisy unisons and incorrect notes.
Other factors that affect the tuning stability of or de-tune a piano are exposure to:
- direct sunlight or HVAC airflow
- outdoor air from open windows or doors
- moisture from bathrooms or kitchens close to the piano
Frequent and/or loud playing will also throw a piano out of tune.
Furthermore, a major factor in doing so is infrequent tuning, discussed below. Essentially, the more often a piano is tuned, the longer it will stay that way between tunings. As the interval increases to six months or more, the strings get used to being in an out-of-tune state in terms of tension. Thus, when the piano is finally tuned, the strings want to return to their former out-of-tune tension in short order.
PART 3: FREQUENCY OF PIANO TUNINGS
With respect to the de-tuning factors above being present in most homes, families with acoustic pianos used by children don’t have them tuned often enough. As a result, the instrument may only sound good for a few weeks throughout the year.
(Due to teaching remotely and listening to students’ acoustic pianos for over a year and a half, we can personally confirm this to be an irrefutable fact.)
In particular, piano technicians usually recommend 1-2 tunings per year, which makes budget-conscious parents happy. In contrast, concert hall pianos are tuned one or more times per day, and sometimes, during the intermission. How can this be if pianos stay in tune for at least six months?
Apart from the fact that concert pianists usually play more loudly than students, the solution to this mystery is a matter of common sense:
A piano should be tuned whenever it’s out of tune.
Since this is not affordable for most people, a reasonable compromise for pianos in Minnesota is three times per year, as follows:
March/April (as soon as temperatures are consistently above freezing)
June/July (as soon as the air conditioning is running frequently throughout the day)
November (as soon as the heat is running frequently throughout the day)
PART 4: MAINTENANCE OF TUNING STABILITY/TONE QUALITY AND PROTECTING YOUR PIANO FROM DAMAGE
To make each tuning last as long as possible, the humidity surrounding the piano should not fluctuate more than 5% up or down from a particular set point.
We prefer an average of 45%, which means that ideally, the humidity would not drop below 40% or rise above 50%. During the heating season, maintaining 45% may fog up windows and cause moisture buildup on the walls. If so, 40% is acceptable during that time.
Also, pianos have about 10,000 parts. Many of these are made from wood/leather/felt, and in some cases, adjusted to tolerances as small as 1000th of an inch. Thus, limiting humidity fluctuation allows the piano’s moving and stabilizing parts to function properly year ’round. In contrast, expensive regulation work will be needed to correct problems with a piano subjected to the opposite conditions.
Avoidance of low humidity (below ~30%) also prevents cracking and warping of wooden parts, de-crowning of the soundboard (which degrades the tone of the piano), etc., etc.
What’s less commonly known is that a dried out piano loses some of its beauty of tone. In addition, the keys may move too freely, making the volume/tone of notes difficult to control.
High humidity (above 60%) causes wooden parts to swell up, making the keys feel sluggish. It can also cause the tone to become somewhat soggy. Subsequently, if the humidity drops into the danger zone below 30%, the same parts shrink.
This creates the kitchen sponge syndrome, which expands with water and then dries out in its absence. As we all know, the sponge loses its symmetrical shape when the latter occurs. This is essentially what happens to the wooden action parts of a piano when steady humidity is not maintained.
Furthermore, after about a year of steady use, the hammers of a piano become excessively hardened. This usually makes the tone unacceptably harsh or bright. In turn, the piano’s ability to produce a wide range of volume levels and tone colors is significantly limited. The solution: a piano technician inserts needles into the hammer felts, thereby restoring their original resiliency. This service is referred to as a “hammer voicing” or “voicing“.
PART 5: DON’T BUY AN ACOUSTIC PIANO UNLESS…
We recently heard a recording of a student’s piano playing at home, and heard that most of the unison notes had the ugly jangling sound discussed earlier. This explains why, in their lessons at our studio, the student had difficultly controlling volume and tone quality on our grand piano. (This piano is fully tuned at least four times per year and touched up as necessary between tunings.)
Ultimately, piano lessons are about learning how to play an acoustic, and thus, the ideal learning situation is to practice on one.
However, unless you’re willing to invest about ~$700 a year in tunings, hammer voicing and keyboard/action maintenance, most of the time, your child will be practicing on an unpleasant sounding instrument with an uneven key touch response. (Our remote lesson teacher witnesses this on a weekly basis for the student who has an acoustic piano.)
In sum, the problems directly above interfere substantially with meaningful musical advancement. In short, they can learn to “hit the notes”, but that’s about it.
As a bottom-line alternative, we recommend a Casio PX-870 with a subwoofer, vertical stand, and pedal board. This digital piano configuration costs about $1000, has a good tone, a decent key action, and rarely needs maintenance. Note that the subwoofer is especially important for overall depth of tone and bass response, as affordable digitals have small built-in speakers.