G'day all,

Duo-Art dynamics have certainly generated some "loud noise" in this
forum, most of which has been very constructive, except maybe my
reference to earplugs!  It is clear that "too loud" is very subjective
and those in the audience not actively listening are very likely to find
the volume of typical live or recorded playing a little uncomfortable.

But, getting down to basics, when I first rebuilt a Duo-Art some years
back, I used the Vestal Press Technical Series Number 5 (by Michael
Kitner) as a guide.  What puzzled me at the time, and still does, was
his zero-setting procedure.  Michael used the regulating screws to just
begin to close the regulator pneumatics and then setting the vacuum to
5" using the regulator spring tension, later making corrections using
the test roll.  He claims this method reduces the chance of loss of
expression control.  Do the possible higher spring tensions result in
higher vacuum at the top end, or does it just affect the operating range
of the regulator?  He ends up with vacuum around 40" at the top!  Maybe
with a well restored action, the results are similar with either method.
Has anyone tried this and made a comparison?

On the topic of hammer voicing, one hammer on my 1921 Steck has been
replaced in the past and is noticeably softer.  A full replacement would
make quite a difference to the sound, but probably only a few dB to the
total loudness.  Something else to consider is the unwanted mechanical
sounds which will be more noticeable with softer overall playing.  Life
is always full of tradeoffs.

Another question:  In the past, I have used synthetic (Bilon?) material
for the accordion pneumatics because it is supposedly more stable.  The
job was done over 10 years ago and has given no trouble at all and has
rarely needed readjustment.  The Steck was done by someone else about
the same time using leather which is now deteriorating and needs
replacing.  Should I use leather again or synthetic?  What are others'
experiences?

Thanks,¶
Darrell Clarke