I have installed many pairs of these ( the 901 came in series 1 thru 6 throughout it's time ) in my early days of audio, and owned a pair, connected to a modified GAS Ampzilla amplifier. I suspended them from the ceiling, in all cases ( inverted, as the connections faced upwards and the holes for the eye hooks were pre-drilled). Based on the listeners seating distance from them, and the room size, determined how far we hung them from the rear wall. I was invited to a BOSE presentation for members in the industry ( at a forgotten hotel in Manhattan ), and during this presentation, they took a pair of bare electrical wire ( similar to what you would find on a coffee maker ) with an ac plug on one end, connected and plugged the 901’s into the ac outlet. They left the 901’s plugged in for 1 minute, with a sound, I will never forget. Afterwards, they connected them back up to the Crown amp they had on hand, playing music, and they played fine. This was to demonstrate, the durability of the voice coils, the drivers, and, the use of no crossovers. Passed ! Anyway, as no speaker is perfect, I have to say, they did do some amazing things, particularly, their power output, and their huge stage presentation. With a flat, bare wall behind them, they were fun. Enjoy ! MrD.
