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.
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.
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
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 -
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.