Full Range Drivers

To get the most out of a single driver, you also need a huge, sometime elaborate enclosure.
And yes, the best can run some real $$$. But, given the generally high sensitivity you won't need a gigantic amp.

I have owned many speakers over many years and have enjoyed several single driver speakers including:
Beauhorns, Lamhorns and KCS seas exotics. None of these are full range in the sense of 20hz-20khz...not even close.
But depending on the room, positioning, music and personal tatse, I have found them all very satisfactory and satisfying...in fact, I would consider the KCS seas exotic to be one of the very best values I have come across.
I currently use Tonian Classic 12.1s which use the PHY driver covering most of the speakers usable range and the treble is brilliantly handled by the Raven 2 ribbon tweeter. This being second pair of Tonian speakers I have owned (original TLM-1s) and a very fine speaker IME.
I certainly like what a well designed single driver speaker can offer but like all speakers you have to pick your priorities and poison.

I ran Fostex Fe166 in a fostex BLH cabinet that I built for under $500 total, ran it with a Thorens TT, Bottlehead preamp and phono and Fi X 2a3 amp. It was one of the most enjoyable systems I owned. Very coherent, music that hangs in the air and very ballanced from 45 to 15k.

This is the system I most regret getting rid of in my search for the best. It was a 3K system that played music like an instrument and volcals like the singer was in my room

Fin1bxn. That's what I'd like to hear is vocals like the singer was in my room. I'm toying with the Tekton Kat's Meow. The price is great and the designer/owner of the company said he'd pay to see the look on my face when I compare them with my B&W CM7's. He has a lot of back ground working with various speaker manufacturers and it sounds like he knows what he's doing. With a 30 day money back guarantee and a 5 years warranty, why not have them around? I'd like to be able to chose speakers based on what music on want to listen to.

One thing that should be made clear is that "Full Range" is a bit of misnomer for the average listener of moderate income and room size. Very, very, few speakers of any driver design actually cover 20Hz-20kHz(-3dB) accurately. Very few do 30Hz(-3dB) accurately. Those that do are usually very big, very heavy, and very expensive.

Fullrange single drivers have their advantages and limitations. I think the first sonic benefit that most fans, like myself, will tout is their musical "coherence". What does that mean? That the entire musical spectrum seems to emanate from one, seamless, sonic tapestry without any inconsistencies. It's very hard to describe in words, but once you hear it, it is very hard to accept anything else.

Why do they seem more "coherent" to some people than other multi-driver designs? I think most of us, like Macrojack, will cite no, or 1st order, crossovers and no need to transition between differing drivers at the crucial midrange frequencies where the ear is most sensitive to anomalies. Seamless transition between drivers of different size and construction materials is not easily done and fairly rare.

The downsides - like all speakers, bass. There are only three ways to deep, accurate, bass; 1) large driver surface area, 2) long driver excursion, 2) big cabinet. Usually, two of the three are necessary unless lots of power is needed.

And single drivers generally need really large cabinets to go deep with any authority. Even then, they won't move the same amount of air as good multi-driver designs. But, well-executed designs will have very fast and clean bass, which can be supplemented by good subwoofers.

Which brings us back to - is that really a single driver system? No, not in the strictest sense. But, single driver advocates are primarily concerned with a driver covering the most critical section of the frequency range in it's entirety - the full midrange (400Hz-6kHz). Most single driver proponents would even like to push that out to 8kHz-10kHz.

BTW, Tannoys aren't single drivers, they are coaxials with a center-mounted tweeter. But, their 12' or 15" driver does cover the entire critical range anyway. And they are pretty awesome when properly implemented in the right cabinet.