fenderbender:Maybe Groomslakearea51 will chime in. He went acquired a pair of 901 series 1 a while back and tested them up against everything he had in the Klipsch lineup. I believe his comments were that if you had a room full of people milling around, the 901's were kinda ok, but couldn't touch any in the klipsch lineup.
Chiming in... 
I took some time to think about this in the context of the thread, so it's just my opinion...
First, and to be clear: IMO, the Klipsch Heritage series are the best speakers ever made. I cannot testify to Palladiums or Jubilees (yet), but based on the Klipsch "track record", I would not have any worries on that evaluation... I've had a boatload of speakers (probably more than Colter over the last 36 years!!) many of which which were very good (AR's, pairs of Altecs, etc.), but hands down when you compare everything (including how easy they are to maintain, tweak, etc.), they are simply the best. Some would argue some of the esoteric, >$20k types, and that's understandable, but $ for $, you just cannot beat a Klipsch.
The "901" point I would make, or throw out there for some thought is basically, and without the usual "let's just bash Bose", if someone want's to consider the Bose 901's, it's going to be the application. Notwithstanding the room environment, and how they are driven, the 901's have a particular application parameters, and unless they are used within those, they will not sound good, at all..... .
Some background... Back in the day.... I had 901's (2 pairs, stacked...) and bought them new in 1971 in the PX (got'em cheap because they were the demos with the scratched tops, etc.) when I was making the really big bucks on active duty. I drove them with Sansui AU-999's, and sold them in 1975 when I got all sophisticated and bought JBL 4311's and 4312's. I kept those and in 1979 got really upscale and bought my first pair of Klipschorns (KC-BB's). Had those, a pair of 78' Heresy's and assorted JBL's until 2004. Finally sold the JBL's (to some folks who lived in Taiwan as I recall) because I could not get replacement drivers from JBL anymore, and ever since "collected" Heritage series.
Meanwhile, for no reason other than just having the opportunity, last month I picked up a pair of the original 1968 Bose 901 Type-I's for $300. Oiled walnut, surrounds were the original fabric, and still in pretty much mint condition. The equalizer worked pefectly, etc. So.... and having had Bose 901's, and knowing that placement, amps, and in particular knowing that the equalizer has to be set correctly..... I did some experiments with them in the "man cave" as the "centers". I use the same amplifier types as the K-horns, LS's, Forte's, Heresy's, etc. and started fiddling around. Now once I "dialed in" the distance between them, the height off the floor, and the equalizer setting, they sounded just fine. But.... in that specific application.
Maybe I should say something about that now. I like sweet spot listening and do it often; but sometimes I just like the "concert hall - wall of voodoo", and for that effect, I use multiple amps and multiple speakers. It's a "heresy", I know, but it works for me (key thing here is "works for me"... ). I've had a number of guests (forum members) who have listened to the wall of voodoo, and they generally agree that for what I'm doing, the volume levels, etc., it works.
So in my case, or from my perspective, it's the application.... As an example, in the master bedroom (old wall of voodoo - but now the "wall of boudoir"...), the LaScala's (in the center), along with a pair of K'horns in the corners and an Onkyo AVR do the HT thing for my wife. She loves it; they look nice and pretty, and sure sound great. The Belles? When I get finished, they will be the bottom "centers" with a pair of Heresys up top side on the HT set-up in the living room. Unfortunately, there is no place for K-horns in that room, absolutely no "free" corners. Now to be sure, I tested the 901's in the "living room from hell" (no corners, vaulted ceiling, half height open center wall, etc) and while I can get them to work, would require a major re-alignment of the room's furniture, etc. It does not matter if they are Bose 901's, Klipschorns, etc., that room's solution is restricted by the geometry of the walls, etc. I'm stuck with Belles or Cornwalls or Heresys in that room's configuration, and then only on one side of the room. My son's room, however has corners, and the original "KC-BB black beasts" I bought in 1979. He's happy and while the room is small & "cramped", they work, and work well. So, as one can see, it's an "application" driven hobby for me. Right tool for the job analogy....
How do the 901's compare to Heritage? It's like, to me anyways, like trying to compare the steak to the salad on the dinner table. On a "one on one" they cannot do what Klipschorns, LaScalas or Belles will do. The 901 design is just not for that. And that's the key to the 901's....
I read (and re-read) again... the 19 January 1968 instruction manual (16 pages!), and the original Hirsch-Houck Labs (Julian Hirsch) reports from 1968, and the E&E Lab reports that are with the original documentation. The "clue" so to speak, is in those reports. To paraphrase Mr. Hirsch, the 901 is really good, but it's designed for a wide dispersion sound stage effect, or in other words to create an auditorium effect, and generally within the room to mimic the sound that is about mid-audience area. Hirsch was honest in his evaluation and basically inferred that by design, they do not have the generally desired "sweet spot" effect (like Klipschorns and the others...). He (and the others) noted that proper equalizer settings are absolutely critical to make the 901's work. They do not have that bass response of any of the horn loaded bins, in particular at very low volumes. But what the 901 does do (and that's what they were designed for...) is give a very good compromise at moderate volumes, and this was an important factor: With a relatively small "footprint.
So.... What good are they? Well.... It's arguable and subjective. What am I going to do with the 901's? Well.... Where they will work well is in that center space (with the exit door in the middle) between the Klipschorns & Forte's. I also found that (like referenced in this thread), that by having them only 12" from the walls works better; height? 24". Stands? No. Don't laugh, but in the man cave, they will be on the tops of a heavily modified pair of Heresy's (K-28's, D250X's, CT-125's and an E/4500 crossover) - Reason, while that center area in the wall of voodoo benefits from the direct/reflecting 901, I still like having that highly directional effect that the Heresys do so well as centers.
Again it is the application and what you are doing with them!! But that being said, all speakers require require proper placement, good amps, etc. And with one exception, most speakers seem to sound "better" with certain types of music, or at different volumes, and in certain room layouts. I would like to say straight away that the exception for me is the Klipschorn. Other than that pesky "corner" thing, it sounds really good all the time, regardless of the source music type, and regardless of the volume. Even at the lowest possible volume on the amplifier, with the mute switch, and while it sounds like it's 2 miles away, it's is still perfectly clear and "balanced". The Klipschorn just simply does it's job, quiet or loud. For that, it is the ultimate "universal" speaker. When I get up in the morning at 0:dark-thirty, and put on NPR and roust the kids, it's the Klipschorns in the man cave that get turned on and I can clearly listen to them throughout the house. Same thing for working in the home office/man cave. If I could convince the boss that I need to put a pair of Klipschorns in my office I would do it....
Would I buy a pair brand new for $1400 plus tax? Nope, not a chance. When I get ready to plop down $1400+ bucks for a new pair of speakers, it'll be H-III's for sure on that one. My theory is that for the same price, the H-III can hold it's own, sound is more "clear" (cannot beat those horns!!!), you can move them around, they don't really have to be critically placed, and you don't have to screw around with an equalizer, etc.
Would I recommend the 901's to anyone. Probably not. Two reasons really, one is mechanical, and the other is because I truly believe that within the Heritage series there is a choice for everyone that can do the overall job and pretty much do it better. The mechanical reason? Several actually: The 901's need that equalizer to work. It requires you to "route" all of your input through the equalizer by way of a tape deck circuit (tape-in - tape-out), and you can only run the 901's off that amp or receiver. You cannot run the 901's and let's say, surrounds, sub, etc off an AVR because the Bose EQ will make them sound awful strange... You can hook another pair of whatevers up, but you have to turn off the 901's and defeat the EQ. That's a pain. What it means is that if you use 901's, then you are going to be restricted to 901's (unless you have multiple amps, and the source is "upstream" from all of them).
The other issue is that the design uses a full range, 35 watt (x 9 of them) long excursion (which is what killed the older foam surrounds...) driver. Until the volume gets up a bit, the reflective technology does not overcome the dampening effects of the walls and the room acoustics. That's probably the reason so many folks say they suck or sound "muddy" at low volumes. Even the EQ cannot compensate across the board for that problem at low volumes. For consistently low volumes, you have to set the EQ just right. Then if you turn them up, you will have to re-adjust the EQ and turn on the 40hz filter, and change the HF level. Now that's a pain. The other issue, and Hirsch pointed it out, is that driving all of those 18 x 35 watt drivers takes a good amp. Back in 1968, he recommended at least 60 watts RMS, and suggested that 200 watts would be more the ideal. By nature of it's design, the 901 is not an "efficient" speaker in the sense of the Klipsch horn loaded designs. You could, I suppose, run them with a 10 watt tube amp, but..... what's the point?... because you could never get them loud enough to appreciate the intended "effect" for which they were designed.
When Dr. Bose was an engineering grad student at MIT, his whole focus was on developing the reflective part of the technology to create the large space "auditorium" effect, much more so than concentrating on a pair of speakers that relied upon the location of the listener as the classical designs generally required. To that end, yes, the 901 is a successful design, but it has it's limitations, and that's where the "let's compare" problem lies. I also think that one of the problems that Bose has with the 901's is their marketing approach. For so long they have touted the 901 as the "finest", the "best", etc., but without emphasizing why they were designed and what the buyer is going to do with them. They (or their dealers) also hurt themselves by generally only demonstrating them in carefully constructed and treated rooms with specific source material, etc. Buyer gets them home, expects a duplication of the precise set-up they saw at the showroom, and of course they "suck". An analogy would be to "forget" or failure to make sure a Klipschorn buyer fully understands that yah gotta' have them in them thar corners....
If someone tells me they are going to buy a pair, after the usual "why not Klipsch?" discussion, I will certainly ask them to describe what they are going to do with them. What type of sound are they looking for? etc. Again,, it's the application. Even if someone has a line on a really nice used pair and their heart is set on them, I'd always tell them to stay away from Series II through early Series VI. Reason, as pointed out in the thread, the surrounds rot out. Bose knows it and about 2-3 years ago, they went to a completely different type of driver construction. They were getting really bad press because of it and they were embarassed. They now use a type of surround material that will not deteriorate. The 901 is their "flagship", and they are very sensitive to bad press or bad opinions about the 901's.
In substance, one could conclude that the 901 has a specific type of application, and other than using them in that environment for which they were designed, they will have "issues". When I mentioned to fenderbender that they are intened for a room full of people, or let's say a room where you and everyone else are moving around alot, or a room in which the music is more of a background (or maybe better described as supplemental) rather than the focal point of the gathering, then ok, that's the application for which they are intended. Unfortunately, for Bose...., is that you can do the same thing with respect to having a system that you would use for that "supplemental" music, but get the better resolution from a pair of Klipschorns, LaScala's, Cornwalls, etc. for the main event which is, when all is said and done, just sitting down and listening to music.
Hope that is of some interest. Again, only my opinion based on my experience with the 901's and being able to compare them with Heritage speakers.
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