Felt quality

[Serge Harel]

The main difference between NY hammer felt and any German felt is the
density of the strip they use.
For German in the strip of felt you got less density in the bass and much
more density in the treble and the NY hammer felt is low density all the way
with this type of felt you could not presses a hard hammer head and because
the felt price is by pounds It is cheaper. 
 
What I can said is the difference between Grade A and AA from Wurzen is the
type of felts they use for the AA has finer fiber 19 micro and less in some
area and this is more expensive fiber and the felt is more expensive.
The felt for hammer head in Germany is a bend of different felts from all
around the world each one has different propriety the mix in the bass is not
the same that in treble and blend is different between Grade A and AA and
they are make of continuous layer of felt that main that the plate of felt
is sand to the right thickness like other do and it is very difficult to do.
 
The Grade AA is designs for the high tension hammer if you don't have
tension with this particular felt you lose many good thing for the quality
of sound. The are other things that I know but it is secret.

I do make cold presses hammer head with a special Wurzen AA with a lot of
tension they do not need voicing at all but I got a very low capacity of
production. I use authentic Alfred Dolge presses renowned for the tension
they give to the hammer in the gluing process.

I suggest you to invite Jack Brand from Wurzen for a class about felt at
yours next National PTG show.

Serge Harel





-----Message d'origine-----
De : pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] De la part
de David Love
Envoyé : 15 octobre 2007 10:22
À : 'Pianotech List'
Objet : RE: Felt quality

Yes and no.  I think it's slightly more complicated.  A Steinway hammer
which is so soft that it requires a full immersion is different than a
slightly soft hammer that may need reinforcement only on the
non-string-contact part of the hammer.  I'm not sure that it's that easy to
tell the difference or that in the later case the sound is qualitatively
different from a non-lacquered hammer--at least at the outset.  Of course, a
hammer which is softer to begin with will have a different sound than one
that is harder to begin with (especially between molding and crown) but
since the harder hammer is often needled down and the softer hammer requires
some playing time to develop properly, the ultimate difference may be
negligible and the lacquer, at least when applied to the shoulder area only,
may not provide a substantial difference.  At least that's my experience.
Over time may be another story as the lacquer continues to harden and the
shoulders lose some flexibility.  That's my main complaint.  Of course, when
you do need to harden the hammer under or onto the strike point I believe
that does change the character and even more so in terms of how the hammer
ages.  

David Love
davidlovepianos at comcast.net 
www.davidlovepianos.com

-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Richard Brekne
Sent: Monday, October 15, 2007 12:12 AM
To: pianotech at ptg.org
Subject: Felt quality

JD / Dale

And here you have the real reason for doping hammers.  Its a matter of 
taste... purely subjective in nature and if done well will produce very 
nice results that are somewhat different in end resulting sound. 

There used to be a lot of folks trying to justify doping hammers by 
asserting that you could get the same sound as needled hammers.  I am 
glad I dont hear this kind of thing anymore myself, because it really 
isnt true to begin with, and secondly... who should need such a 
justification to begin with ? Steinway NY states outright that they dont 
get the sound they want without using soft hammers built up with lacquer.

Dale and I have had many a talk on this subject and tho we have 
different preferences... I'm know for a fact he gets a very nice sound 
out of his approach.

In the end... regardless of the strong opinions any of us hold... piano 
voice and response is a very subjective thing that has nothing at all to 
do with what the instrument was designed to do... what level of 
loudness/harshness  or softeness/mellowness is achieved.  One persons 
noise is anothers heavenly harp.

Cheers
RicB