The modern standards for air exchange rates are ridiculous. They were dreamed up by the Heat/Cool industry to oversell capacity and complexity so as to generate long term contracts higher than need be in cost. I despise them and many vocalist do as well. I remember when Leontyne Price came to give a recital in our "old" opera house. She demanded the system be shut off just before the concert. It got warm by the end of the show but not bothersome at all. The sound was also much better.
The new hall built for the Seattle Symphony, Benaroya Hall), about 20 years ago has return air plenums under the seats and there is a space cast into the concrete floor of a few inches that encompasses the entire floor. So the air mass moves as a unit with virtually no eddy currents to disrupt the acoustics. No "whooshing" sound
either.
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Edward McMorrow
Edmonds WA
425-299-3431
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Original Message:
Sent: 06-28-2019 18:02
From: Fred Sturm
Subject: Singing doors at the recital hall, slightly O.T.
Yes, one of the joys of HVAC systems is balancing air pressure. Our recital hall has negative pressure relative to the rest of the building, so if a door is left ajar, it will slam shut. There are issues in the rest of the building as well, so there are constant hums of different sorts depending where you go. I remember as a student hearing the recording engineer complaining about the "Keller Hall hum," and being baffled as to the source. That's what it was, and continues to be.
Fred Sturm
fssturm@comcast.net
www.artoftuning.com
http://fredsturm.net
"Tradition is not the worship of ashes, but the preservation of fire." -Gustav Mahler
Original Message------
I arrived at the university recital hall to tune for a concert, and hesitated to enter. It sounded like a choir doing sustained chord warmups.
But no, it was my arch nemesis, the HVAC system, which at least had the decency to turn on BEFORE I started tuning, rather than half way through.
The singing doors:
https://youtu.be/vLB4zN0ovlA
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Greg Graham, RPT
Brodheadsville, PA
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