FAQs (Frequently Asked Questions)

There are actually several factors that influence the tuning on a piano. The primary factor is usually the ongoing and seasonal fluctuation of humidity in the air where the piano is located, which causes expansion and contraction of the soundboard as it absorbs and releases moisture in response to changes in the ambient air. The thousands of pounds of downward pressure of the string set bearing against the soundboard assembly react to this movement, in turn upsetting the delicate balance of tension across the scale of the piano. Fluctuation in temperature may also affect the tuning if the degree of change is great enough, but by that time the side effect of such a change in temperature would typically be a proportional change in humidity level as well, which then likely becomes the major factor.

Second, with as much as 40,000 pounds of total tension loaded onto the 220-or-so strings in the piano, it is only a matter of time before the laws of physics take effect, and the amount of potential energy stored within those strings and their supporting structure will gradually dissipate as they seek to return to their original, unstressed state—not entirely unlike how a balloon eventually deflates or a battery loses its charge.

A third factor, playing the piano, could be described as an accelerating effect on the previous two factors, or as a contributing factor in its own right. A properly tuned and stabilized piano should be able to withstand a reasonable amount of repeated striking of piano hammers against strings; but as time goes by, and the soundboard fluctuates, and string tension slowly dissipates, and strings are repeatedly hammered into motion, this can only hasten the process of going out of tune, at least to some degree.

The piano owner is often given a stock answer to this question, such as "every six months" or "at least once a year." The problem with this approach is that it does not take into account a number of variables involved.

First, every piano is inherently different in terms of tuning stability. I have seen pianos that hold their tuning reasonably well for a year or two or longer, while others go out of tune noticeably in just a few months or less. Interestingly, either of these extremes could apply to top-quality Steinway grands or to inexpensive spinets as well, although there is often some correlation between piano quality and tuning stability. But that is just one of several factors, and ultimately the unique "personality" of the individual piano will have the final say on how well it holds its tuning.

Second, piano environments vary, not only from region to region, but also from building to building—from variations in heating systems and the energy efficiency of buildings, to individual preferences and habits in indoor climate control.

Third, the individual nature of every piano owner or player can also be an important consideration, including the sensitivity of their musical hearing, the level at which they are studying and practicing, as well as their personal budget for tuning.

This is why I approach each client and each piano on a case-by-case basis, taking into account all of these variables in order to arrive at a service plan that is best suited for that particular client and piano.

One of the perennial misconceptions surrounding pianos is the widespread notion that the process itself of moving a piano will affect it in such a way that will require having to get it tuned after it has been moved—whether from one room to another, all the way across town, or farther.

The reality, however, is that if a piano is properly handled and transported (not subjected to excessive jarring, or dropping), the actual process of moving it should have little to no effect on the tuning. But if the move involves a significant difference in humidity and temperature between locations, it is quite possible that the tuning will be adversely affected after a period of time (see the following topic for more). That said, I have heard reports of a piano's tuning being noticeably affected after it was moved—whether that was a direct result of moving versus other factors would be hard to say without a technician closely examining the tuning before and after the move... but it wouldn't be the first time one was surprised by the nature of pianos. Either way, an honest technician could evaluate the tuning after a move to determine if tuning is warranted in that case.

Again, there are multiple variables to be taken into consideration before deciding on a timeframe. The first one is simply how determined you want to be in trying to maximize the stability (and longevity) of the initial tuning after moving.

Second, if at the time of the move there is a significant difference in climatic conditions between the starting location and the destination (such as moving a piano from Arizona to Florida in the summer), you may want to give the piano anywhere from three to six weeks to acclimate. If the move is local or between similar climatic regions, and involves two indoor environments that are not drastically different in humidity and temperature, one or two weeks may be enough. If you are simply moving the piano between rooms of comparable humidity and temperature in the same building, it may not be beneficial to wait at all.

The ideal relative humidity level (RH) for a piano's environment is typically stated to be somewhere in the 40%–45% range. In fact, the humidistat control unit of a Dampp-Chaser piano humidity control system is calibrated to maintain an RH level of about 42% within the piano.

However, the specific RH level of a piano's environment is actually less important than the consistency of humidity level and avoiding extremes. Fluctuation in humidity is the primary factor causing a piano to go out of tune, while extreme wetness and dryness can be harmful to the action, soundboard, pinblock, wood structural elements, case, and finish.

Another consideration in climates with cold winters is that it can be impossible to achieve an "ideal" humidity level indoors without excessive condensation of moisture on windows and outside walls eventually damaging them. In this case, it is recommended to humidify a room or building just enough to create only minor to moderate condensation on your windows, depending on their thermal insulation quality. To achieve maximum tuning stability and optimal protection from extremes, you would then need to have an internal humidity control system installed (see the following topic for more).

There are two primary reasons for having a humidity control system installed on a piano. The first is to minimize the destabilizing effects of humidity fluctuation on a piano's tuning (and sometimes action). Properly installed and maintained, the system can have a moderate or higher degree of influence on how long a piano will stay in tune. But since every piano, owner, and environment is unique, I may suggest waiting until about two or three tunings have been done before deciding to have a system installed. This is to accumulate some service history and data on the piano, as routine pitch, temperature, and relative humidity measurements can be very helpful in determining if a system is warranted and likely enough to improve the stability of a particular piano.

The second reason for having a system installed is to provide greater long-term protection against humidity fluctuation and extremes which can potentially cause serious problems for a piano over time. Think of this as a sort of insurance—while a piano may never develop any major issues, there's a good chance that a properly installed and maintained system will minimize and even prevent such issues.

Finally, you should also be aware of the possibility of misinformation concerning piano humidity control systems which occasionally finds its way to the unsuspecting piano owner. On one extreme, I have heard of clients being told that not having a system installed spells certain doom and imminent destruction for their piano. Of course this is simply nonsense and nothing more than a shameless marketing tactic designed to increase sales of systems with little regard for the best interests of the client. And on the other extreme, I have also heard of claims being made that having a system installed in a piano may actually be very dangerous and harmful to the piano. In fact, in order for that to be possible, the system's electronic humidistat control unit would have to experience a malfunction that caused either the humidifier or dehumidifier component to run continuously, uncontrolled, for an extended period of time. While I'm not even sure if this is possible, I do know that I have never heard of a single instance of this happening. Chances are this claim is rooted in past practices of technicians unwittingly installing dehumidifier rods on pianos without the accompanying control unit. Of course, this is a dangerous practice, but has no bearing whatsoever on complete systems that are properly installed.

For so many years, the conventional wisdom has been to avoid placing a piano on an outside wall. However, unless the house or other building is so old or for some other reason has outside walls that are so poorly insulated from the outside air that one can really feel a major draft when walking near the wall on a cold winter day, chances are an outside wall will be as good as any other. But there are definitely some locations and situations that should be avoided.

First on the list is anywhere that a heating register is going to be consistently exposing the piano to a direct flow of warm air, especially if the soundboard is the immediate target of this flow, since it is more susceptible to temperature- and humidity-related problems, ranging from tuning instability to cracking and other types of failure. Forced air systems are probably more potentially harmful than the others, because the continuous movement of air accelerates the drying process. Placing a piano (and especially the soundboard) in the direct path of cooling system registers should also be avoided.

Second, direct sunlight can sometimes be a problem, depending on the intensity, frequency, and duration of exposure. Sunlight can gradually cause the finish to fade or develop other issues, and if beaming directly on the soundboard, can actually affect the tuning if enough warmth is generated for a period of time.

Also, any other environment that exposes the piano to extremes in temperature and humidity should be avoided. Close to a fireplace or a large indoor swimming pool would be a couple of more obvious examples.