[ Mike Nichols wrote in 131008 MMDigest:

> My question is, is it possible to fit a valve to allow air into the
> expression pneumatic so that it plays at a higher volume?  Something
> like the "Duo-Art On/Off" switch on the Duo-Art?  These instruments
> are very rare in the UK and I am sure there must be an easy fix.

Hi Mike,  I addressed this issue in

  http://www.mmdigest.com/archives/Digests/199607/1996.07.07.04.html 

Unfortunately, all of my back issues of the AMICA Bulletin are packed
away in preparation for a move, so I am unable to provide a digital
version of the illustration(s) that accompanied that article.  Likewise,
I am currently unable to locate my CD copy of the AMICA Technicalities
which should have the referenced article.  Perhaps Terry Smythe or
anyone else with that CD could forward a copy of the article to Robbie
for inclusion here.

John Grant