Ref: Glass and listening areas.
Hello Phil,     My home has what we call a "sliding glass" patio door. The 
was an invention of some really twisted mind in the late 1950s that makes it 
impossible to seal a home from the elements, often jumps the tracks and won't 
close or will stick one time you close it and slam the next time. It consists 
of two glass panels approximately two meters in height and one meter wide 
(each). One panel is stationary while the other slides from side to side on a 
track. They were popular because they do not swing in abd take up wall space, 
thereby allowing more efficient use of your floor space.
        Dual and triple pane glass is often used, increasing the insulation 
factor, but adding to the weight and difficulty in maintaining the seal 
around the door when closed. 
        They are horrible for sound reflections! The sound comes off the 
glass much faster than it does the surrounding wall materials. Covered with 
panels or heavy draperies, the glass panels will easily begin vibrating when 
hit with anything near a well reproduced bass note. So they require constant 
adjustment or "packing" which makes they harder to open and close.
        Nope, sliding glass doors are something you want to stay away from at 
all costs.
Cheers, John
--- Maximus/2 3.01
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