Harmonic Distortion / Overdriving strings?? Noise Question???

[Newton Hunt]

The more resilient the hammer felt the less distortion you should
get.  Hard hammers are the worst.  Get some sample hammers from
Ronson, Isaac or Abel.  With good voicing these hammers will produce
less distortion.  Just my opinion and why I prefer these hammers to
certain pianos.
		Newton

btrout@desupernet.net wrote:
> 
> Hi All,
> 
> I've run into a customer who has noticed a problem with his Boston
> piano.  It's a 6'4" grand.  Playing softly, the tone is good.  But on
> louder playing, and rapid repeated playing of particular notes, there
> comes an irritating sound from the speaking length of the string.  To my
> ear, it sounds like the string is being 'overexcited', or overdriven,
> beyond the point of a clear undistorted vibration.  Kind of reminds me
> of what happens when you overdrive an amplifier and hear the sound
> distort.  On the piano it tends to sound like a zing/ring.  (This is
> like trying to tell a person who has never been sighted what a rainbow
> looks like!)  Upon further examination, I've determined that the 'noise'
> is indeed in the speaking length of the string.  (Blocking out the
> duplex etc. has no real effect.)  Also, I've checked on about a half
> dozen other pianos for the same thing, all the way from Young Chang, to
> Wurlitzer & Baldwin, to Petrof and Steinway.  I was actually able to get
> the same distortions from ALL of them!  The Steinway required the most
> effort on my part to make it give off this 'sound', but I was able to
> get all of them to do it, and over quite a range.  The worst areas on
> most all of them was the range starting about an octave above middle C,
> and continuing up about an octave and a half, but it was indeed possible
> to do this 'overexcitement' over most of the range of the plain wire
> strings.
> 
> I've not been able to put my finger on this one.  Some thoughts to date
> are scattered; hammers are too hard, (voicing seems to help a little,
> but it's still there), hammers striking the string in the wrong place,
> (haven't been able to play with this one yet), too much bearing, (I'm
> not sure how too much or too little bearing would affect distortion of
> the sound), poor scale design, (just because it says "Designed by
> Steinway", it doesn't necessarily impress me), poor bridge notching,
> (the notch does not drop away from the string in such a fashion to give
> a good termination point in my opinion, but I don't know what minimums
> would be.  I know I notch mine a lot more deeply and distinctly when I
> do them.)
> 
> I just wondered if anybody had a thought.
> 
> Thanks in advance.  (And also, thanks for all the good conversation.  I
> just found this list a few weeks ago, and am very happy to be able to
> read the conversations.  I've been learning. (Hope it never ends!)
> 
> Brian Trout
> Quarryville, Pa