The Shure V15 V with a Jico SAS/B stylus VS The Soundsmith Hyperion MR and Lyra Atlas SL

@richardbrand Sorry if you got that impression, but this is pretty basic stuff. The book is really good and would make a good read for any one who wants to discuss speaker design. You bring up useful issues, but they all have boundaries. You can use multiple drivers without comb filtering as long as they are not too far apart. As an example all really great dynamic speakers rely on one tweeter and that is usually the limit on output capability. The reason is that you can not get any good high power tweeter close enough to a neighbor to function as one driver. The motor is too big. This is not the case for midrange drivers and woofers resulting in designs like and extensions of the D'Appolito Array. Even though the midrange drivers are separated by the tweeter they are still close enough to each other to function as one driver acoustically as long as you do not set the crossover too high. My 4 subwoofers have four feet between them. The cross at 100 Hz the wavelength being about 10 feet. Since they are closer than 1/2 the wavelength they function acoustically as one driver and there is no interference between them, also because the line of subwoofers ends at fixed barriers, the side walls, they are functioning as a line source dove to 1 Hz which has further advantages in terms of room interaction. Not to mention it is a gas to hear eight 12" drivers powered by a total of 10,000 watts put out those low synthesizer notes you hear in modern electronic music. It's like twisting the throttle of your Thruxton wide open and shooting off towards the horizon, front wheel in the air. Some people never grow up. 

You listen to "modern electronic music"? Just kidding.

If I lived in rural New Hampshire, I would have a Ducati for sure.

@richardbrand What is a pseudo line source? Do you have stadium concerts down under? If you go to one you can hear midrange/bass line sources. The sound is usually awful. I do not bother any more. 

The problem with most "line source" speakers is that the line source behavior is limited to certain frequencies depending on the design of the speaker. Very few people have a line source system capable of maintaining that behavior below 200 Hz. This is the big reason these speakers tend to lack really punching bass. Point source speakers lose acoustic power by the cube of the distance away from the speaker, but line sources only at the square of the distance. As you move away from the speaker bass frequencies fall off much faster leaving an anemic sound. Full range line source systems have advantages. The sound stage you get is right up from within the first 10 rows. Point source systems are back in the 25th row. Bass and percussion are much more life like in terms of power and dynamics. The problem for most people is the size of the system, it owns the room.

You do not need a distributor. Sound Labs will ship anywhere in the world that allows it. God knows what the duties are like down there. The Aussies make some great equipment. My DEQX preamp is Australian. There are many speaker manufacturers. Nobody makes ESLs? 

I have zapped myself on numerous occasions usually from forgetting to ground out the diaphragm before working on the speaker. That is a bigger zap than what you get from the bias supply directly. It is not capable of much current. The stators are referenced to ground, they discharge immediately when the music stops. 

@lewm Vermont also has great riding, but New Hampshire rules with the Harley crowd because you do not have to wear a helmet here. They think that putting along at 30 MPH means you can't get your head squished by a run away truck or a WOMAN in an SUV on her f-ing cell phone. I emphasized the female gender to make sure everyone knew I was talking about an XX, not an XY masquerading as an XX.  This is particularly true of XXs driving Jeeps. My helmet is fluorescent yellow and it scares the h-ll out of many drivers. They move over even if they are not in my lane, Brilliant. We now have airbag vests. When the vest detects an unusual acceleration in the wrong direction it fires off the airbags and you go bouncing down the road or off other vehicles until the bags deflate. I don't use them too uncomfortable. I would use them for racing, but I do not do that any more in the strictest sense. 

I do own a Ducati, but in this case I was referring to my Triumph Thruxton RS. There are times when the British hit the nail squarely on the head like the Jag XKE and the Thruxton RS. The Ducati is raucous and in your face, but the Thruxton is just a beautiful thing, visually and mechanically. 

@mijostyn 

I do know and understand that stuff, pretty much like the back of my hand.  Absolutely right, subwoofers should be put to work on long wavelengths, which often will be longer than the listening room.  They will excite room resonances and one benefit of having multiple subs is that they average out these resonances a bit.

Now are you saying that the longest distance between any two of your subs is four feet?  I am particularly familiar with the Duntech Sovereign where the blurb says it is "acknowledged by experts as the finest speaker in the world, certainly the most accurate".  Each speaker has seven drivers in a floor to ceiling D'Appolito arrangement, which puts 12" bass drivers near the floor and ceiling.  Base is quoted as down to 27-Hz within 2-dB.  A huge amount of effort was put into time aligning the seven drivers so if you sat at the right ear height, phase differences were less than 25 degrees.

Because time alignment is so important, vertical listening position was crucial.  Slowly lower yourself and suddenly a huge image came into focus.  A few inches more and it was gone.  That was in a very large demonstration room where wall reflections mattered less than usual.  I've mentioned before that the reference used when designing these speakers was the Quad ESL-63.

Yep, the wavelengths tweeters should handle make it unwise to use more than one (why does Infinity spring to mind here?).  Tweeters can be made coincident (concentric) with mid-range drivers, as was done by Tannoy and is now brilliantly executed by KEF.  I have not heard the Tannoy re-incarnation by Fyne.