As far as 64 foot stops go, there are some organs that have them; I think the Washington Cathedral may have one, and perhaps the Wannamaker Organ in Philadelphia. There's supposedly a 64 foot stop and 8hz note used on the M&K Power and Glory LP, although that may be a resultant from two 32 foot stops; my system doen't go low enough to hear it, although I remember some queaziness in my stomach listening to it, so there may be some truth to the rumor.
On the use of an electronic 32 foot stop, we use a tone generator for the 32 foot stop of our small organ in my church. When we got the thing (it's really a large speaker, which you amplify with an amp with a level control), I put it on a wheelbarrow and wheeled it around the church working with our organist to find the spot it would best integrate with the rest of the organ. We wound up putting it above and behind the choir loft, adjacent to the church offices and a large meeting room. When our organist, who loves deep bass, set the amplifier to figure the proper level, he initially didn't realize how sensitive the driver was, and when he played the first 16hz low C he knocked all the pictures off the walls in the meeting room and offices and drove the church staff out of the building fearing that an earthquake had occurred (any of you had that problem integrating a subwoofer?)! It may be cheating, Texasdave, but it actually does work quite well, and is a nice alternative for an organ that doesn't have the space in its chambers for a true 32 foot pipe.
On the use of an electronic 32 foot stop, we use a tone generator for the 32 foot stop of our small organ in my church. When we got the thing (it's really a large speaker, which you amplify with an amp with a level control), I put it on a wheelbarrow and wheeled it around the church working with our organist to find the spot it would best integrate with the rest of the organ. We wound up putting it above and behind the choir loft, adjacent to the church offices and a large meeting room. When our organist, who loves deep bass, set the amplifier to figure the proper level, he initially didn't realize how sensitive the driver was, and when he played the first 16hz low C he knocked all the pictures off the walls in the meeting room and offices and drove the church staff out of the building fearing that an earthquake had occurred (any of you had that problem integrating a subwoofer?)! It may be cheating, Texasdave, but it actually does work quite well, and is a nice alternative for an organ that doesn't have the space in its chambers for a true 32 foot pipe.