[ Roger Wiegand wrote in 051008 MMDigest:

> Would there be other unintended consequences of blowing cold air
> into a warm pipe?  Would it actually solve the intonation problem?

I think it would cause many more intonation problems.  Before playing,
the pipes are sitting there, filled with the ambient temperature and
humidity air.  When playing begins, certain pipes will get a dose of
your conditioned air.

As each pipe continues to sound, it will slowly fill with the freshened
air, and slowly change its pitch.  The yet unplayed pipes will still be
at ambient, and the first time they are played, will play at ambient
pitch.  And meanwhile, the pipes that played first will begin
re-absorbing ambient, etc., etc.

Have you ever wondered why a real steam calliope never sounds quite
in tune?  It's because as a pipe is blown with steam, it warms up,
then it cools off during rests.

The most important thing, in my opinion, is to make sure your blower
does not heat up the air supplied to the organ.  Blow the organ with
air as close to ambient conditions as possible.  You could surround
the organ (at least the trailer front opening) in a visually and
acoustically transparent plastic sheet, the air-condition the whole
insides of the trailer, and feed the blower from that.

Best is to arrive a few minutes early and touch up the reed pipes.
The flue pipes will all go up and down in pitch together.

Mike Knudsen