odd harmonic

[Richard Moody]

While a Samick is not a Steinway, I encountered the problem you
describe.  The bass strings were "leaking" harmonics all over the
place because of the dampers below the notes being played not working
properly.  A quick check for this is to mute the first 7 bass strings
with a gloved hand to see if the after ringing is surpressed.   I then
pressed down on the damper heads and the " ringing" would stop as if
the dampers were not heavy enough. But I noticed an odd feeling while
pressing.  The dampers seemed to be blocked from going down further
onto the strings.   Well the damper lift lever was on the the damper
lift rail.  This was readly apparent after the action was out.
Lifting the damper rail by finger immediately moved the dampers.
There must be a "gap" here but there was none.
    In the Samick there are capstain screws under the individual
damper lift levers. It seems one could turn these to get precice
damper lifting without having to do the wire screws and setting the
level of levers that way.  It took so much turning of the capstains I
wondered if I should set damper wire screws instead.

So my suggestion is to check to see where the damper lift levers are
in relation to the damper lift rail.  Testing for lost motion by
pressing the pedal  will not show a gap between the lift rail and the
lift levers.  As the damper felts compress from resting on the strings
you can visualize how the damper lift levers will lower toward the
lift rail.
If they touch the lift rail the damper is not seated as much as it can
on the string.   This mimicks tight damper guide rail bushings, tight
lift lever flanges, and mis aligned dampers because of tension from
the set screws acting on the lift wire and worst of all, lift wires
that are not bent right.
===ric

Ps if there are individual dampers ringing here and there but with
free rail guides and free lift flanges, fluff them up with a voicing
needle.



----- Original Message -----
From: Lawrence Becker <lawrence.becker@uc.edu>
To: <caut@ptg.org>
Sent: Thursday, April 04, 2002 6:25 AM
Subject: Re: odd harmonic


| At 11:01 PM 4/3/02, you wrote:
| >Hi all: Twice this month I have come across pianos which hum a
harmonic 2
| >octaves and a seventh above the fundamental when the key is
released. In
| >both cases it was only one of the three strings which leaked the
harmonic,
| >in both cases an outer string. I checked and re checked the string
level.
| >Any ideas? one was F# 2 on a S&S B, the other was D3 on a S&S D. I
have
| >tuned the D for years- this just showed up.
| >---
| >David Graham <dcgrpt@earthlink.net>
|
| David-
|
| I would check the duplexes.  The back is probably strip-muted, but
I'd
| press on it and the front with my finger while playing the note.
With the
| back duplex, it doesn't have to be the note you're playing--can be
pretty
| far up the scale.  Also, plucking the offending string while the
damper is
| seated.  Those trichord wedges can have unequal sides.
|
| Troubleshooting Steinways: it's not just a job; it's an adventure!
|
| ----------------------------------
| Lawrence Becker, RPT
| Piano Technician
| College-Conservatory of Music
| University of Cincinnati
| ----------------------------------
|