Restoring pitch to a piano goes by several names. Terms such as “pitch raise,” or “re-pitch” are the most common. No matter what it is called, it refers to raising or lowering the pitch to a standard frequency level, usually 440 cycles per second at note number 37 (middle A) on the standard 88 note piano keyboard. Modern day pianos, those built after 1900, are engineered and built with this pitch level as the tonal frame of reference. Most bands, orchestras and choral groups in America use this pitch reference regularly as their standard. Hence, the term: “Concert Pitch 440.”
A new piano should be at, or near, concert pitch when it is delivered from the dealer’s show room. If you’re in doubt about this, ask a qualified piano technician, music teacher or other knowledgeable music person to help you determine the pitch level of your new instrument.
When a piano has been allowed to change its “pitch level,” away from A=440 more than ten cents (1/10 of a semitone) either flat or sharp, restoring its pitch becomes necessary. This is not only so that the piano sounds good and agrees with other instruments and singers, but also to prevent damage within the tonal parts of the instrument. Strings, bridges, soundboard, and hammers are all affected by the piano’s overall pressure level. These parts respond over time by adjusting to whatever pressure level has been allowed to become established. As an example, the bass strings are weighted with copper wire windings in order to speak their notes within a few cents of the A=440 pitch standard, either flat or sharp. When the piano’s pitch level has been allowed to change, its strings cannot speak their true tones.
Pitch restoration is an exacting and time consuming procedure, and it is relatively expensive when compared to regular tuning care. It should be accomplished by an experienced piano technician who is factory trained and familiar with the techniques in establishing the pitch level when an instrument is being built. As the piano develops its true pitch level, an uneven pressure curve develops and increases exponentially. Pressure must be added to the strings, harp plate, and sound-board in increments, and special care needs to be exercised not to damage these tonal parts. This procedure normally requires 8 to 12 hours to accomplish. When finished, the piano should be allowed to sit (render) for at least 72 hours. At this time, it needs to be accurately tuned, then re-tuned at regular weekly intervals until the new pressure base “settles” and the piano holds its tune. This may take 3 weeks or more. In addition, subsequent tunings and other adjustments such as pin coil staking, harmonic bridge adjustments and tuning pin “set” will likely be required.
It is important to keep your piano in good tune once its true pitch level has been established. Please contact us for questions you may have about your piano and its care.