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For the more scientifically minded...


A HP 35660A, Dynamic Signal Analyzer was used to measure randomly chosen notes from three different ranges in the piano. All scans were made in the same room. An AKG SE300B microphone was used and placed 11 inches above the damper for F#4. All samples are accumulated averages of twenty-five scans. A uniform touch at the key was provided for by a lead weight of 519.1 grams.

Steinway D (Wapin)

A D concert grand built in 1929, rebuilt in March 1996. Includes a new sound board copied from the original by Gibbs Piano in Milford, Ohio. Bridge was modified with the invention. Hammers were concert D from Steinway and were voiced for the concert hall. The action is Renner. Bass strings were made and designed by Sanderson Piano Services in Littleton, MA. Tension is nearly constant from note to note in the area of interest. Tension is between 180 lbs. to 190 lbs.


Steinway D


A D concert grand built in 1984. This is the current king in the concert hall. Artists from around the country have identified it as an above average Steinway D. The only structural change in this piano during its lifetime has been the regulating and changing of hammers. The current hammers are Steinway hammers.


Kawai #90

An EX concert grand purchased in 1990. Has been the king piano in one of our other halls. It is generally chosen over another 1968 Steinway D in its hall.

The graphs on the following page are a simple Fourier Transform showing the relative strengths of the various partials of the note D3 on the three concert grands. Note that the resolution is enormous. It is so large that the amplitudes of first three partials obscure any information about the rest of the spectrum. If this were typical of the way we hear as a species we would probably not communicate by talking. In fact, we would only be able to use our hearing to sense the movement of large objects such as hippos or elephants. We certainly would have no comprehension or awareness of music.


Some observations can be made from the graph above. Note the normal Steinway does have a stronger first partial. It also has a nice look to its relative partial amplitudes that are visible. The top piano, Steinway D with Wapin looks as if all it can produce is a near true sine wave with little harmonic content. At first glance I would choose the Steinway in the middle and then the Kawai on the bottom before I choose the top piano. Of course, the human ear doesn't hear sound quite this way.


Below is the famous Fletcher and Munson curves showing that the response of the ear varies with the frequency of the sound. These curves support the theory that the human ear is generally most sensitive frequencies between the 2000 hz and 5000 hz range. In fact it appears that to the ear, a sound at 1000 hz must be ten times as loud (amplitude) to be perceived to be at the sound at the same level as a 2000 hz sound!


Now lets look at the exact same data that we used in the former graph from our pianos but apply a logarithmic scale - Decibels

Ah!!!!!!…..now there is a perceivable difference!. Especially, note the richer spectrum of the top graph (Wapin). Look closely at the 3000 hz to 6000 hz range. How could it be so good? That's exactly the range to which our hearing is most attenuated (see Fletcher & Munson graph). Too good to be true? That's exactly what we thought when we first encountered the results of Wapin.