I can tell you after an hour of listening that these are not junk, and deserve serious attention and evaluation. My original (series 1) 901s are very well built, with excellent plywood cabinet construction. They pass the knuckle test solidly. All 18 drivers are good, with no deterioration in the original treated cloth surrounds, and are well sealed with putty. Eight 5 inch drivers per side generate a lot of internal air pressure, and the cabinets are up to the stress. There are no crossover caps to deteriorate, because there are no crossovers!
The speakers are not intended to be used without a purpose built equalizer box, which I do not have. I obtained frequency response curves for the series 1 equalizer easily on the internet (including the curve from the BOSE Corporation's patent), and set the curve and saved it as a custom equalization setting in itunes for my initial listening. The curve is extreme, up 12 db at 30 hz, so a powerful amp is a necessity, and the Adcom GFA-1, at 200 watts/channel, fills the bill nicely.
The sound? I listened for a few minutes without the eqaulizer, and as expected, it sounded all wrong, ok in the mids, totally weak everywhere else, just what you'd imagine from looking at the eq curve. With the correct equalization, it sounds tonally right. It's a big, beefy presentation, with good bass and clear tonality, but also different from just about anything else I've ever heard. That's not surprising, considering that 8 of the 9 drivers in each speaker are aimed backwards. I need to experiment with placement, because there is a slight reverberation (duh), that makes the sound seam huge, but is also the main reason it sounds unlike anything else. I understand why many love it, and also why some can't stand it.
The many different ways that so many talented engineering minds have attacked speaker design (planar, dynamic, full range, transmission line, sealed, ported, infinite baffle and numerous hybrids to name some), are what make this obsession of ours so much fun. Never mind the overpriced crap the the Bose Corporation has produced. This was a ear opening design when it was introduced in 1968, and it still is.