Single driver speakers. Are they worth considering ?

I don't mean electrostatic. How close to a full range speaker can you come with single driver ?
In my opinion nothing less than a three way speaker is worth considering. You’re always better off sharing the work
KEF likes to do single driver point source speakers. It depends what you want. Single drivers have less highs but perfect dispersion. A 3way speaker has clearer sound but horrible dispersion. 
I'm not sure what Kef is a single driver but they do have the small coaxial or point source LS50 which is a 2 driver and nowhere near full range.
Not with a cone speaker, a coaxial is a great idea.. Some think it's the best..

A single coaxial driver, yes. Not my cup of tea.. I've heard some good ones though .. Tannoy Speakers..

Of all the true single-driver systems I've heard, the quarter wave back loaded horn systems of Voxativ and Charney are the only ones I really liked because they had reasonably extended frequency ranges and smooth response (not excessively peaky and rough sounding).  I am particularly fond of Charney speakers with the AER full-range drivers.  The Cube Nenuphar was okay too, but, its frequency response was not quite as smooth and natural as the other two and it lacked the upper bass weight needed for large-scale classical music. 

I don't consider coaxial drivers to be full-range drivers, they are two drivers built into the same frame and utilize a crossover like any other two way speakers.  But, they certainly can sound good.  The big Tannoy systems, like the Westminster, are very good sounding.  

I have heard a lot of fine sounding multi-way systems that utilize drivers intended for use in full-range systems as either a mid-range driver or the bass/midrange driver with a tweeter added on top.  I particularly like the Jensen M10 field-coil driver used as a bass/midrange driver with a tweeter crossed in at a very high frequency.

The comment above about full-range drivers having "perfect" dispersion makes no sense to me (I have no idea what perfect dispersion even means, never mind how any system can achieve it).  Given that most full-range drivers are relatively small in diameter for a woofer, they have WIDE dispersion at lower frequencies, but, given that they are large in size for a high frequency driver, they have a very narrow high frequency dispersion and need to utilize things such as a whizzer cone to attempt to spread highs adequately.  What they more or less avoid, as compared to multi-way systems, is comb-filter problems of two or more drivers interfering with each other.  
What they more or less avoid, as compared to multi-way systems, is comb-filter problems of two or more drivers interfering with each other.  
The Comb filtering is what causes dips off axis.  Hence poor dispersion. 
I built these Aveburys by Woden Design, using Mark Audio 12p drivers.
In the UK you can get great advice directly from the designer and from KJF Audio who can supply all the hardware. About £250 for the drivers and other bits and pieces, £80 for the plans, and £150 for quality ply. And the cost of your own time over a couple of weekends. For that money and time it is easy to find out just how great a back loaded full range horn can sound.  If you have the space of course - one of the routes out of the compromises is a very big cabinet. These are 6’ high. 
I'd rather pass a gallstone HA. Actually I have single-driver speakers, of course it's all in the application as anything else. Plus we choose our compromises.
Once you listen to a single driver speaker, you will never go back to a multi-driver speaker that is nothing more than a symphony of disjointed monstrosity :-)
Those Charney Audio speakers look great and have some excellent reviews.  It looks like the company is not too far from me in NJ.

Another single driver variation is the Voigt Tube like what was featured in this Tech Ingredients video:

On single drivers the  frequency response tilts steeply upwards from bass to treble there's Beaming at high frequencies,  top end marred with ripples and IMD is a problem and they aren't full range. Other than that they should be fine. 

KEF likes to do single driver point source speakers.

Someone seems to be confusing single-driver with concentric drivers. 

Tannoy does a nice job with concentric drivers.
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Wow, you’re opening Pandora’s box with this thread!

As with most things audio, I think this is a matter of personal preference more than anything. Any speaker design is a compromise, it’s just about which trade offs you prefer.

For myself, I ran Harbeth SHL5+ for years and thought they were my end game speakers. Until I stumbled into a pair of Omega super alnico monitors. The Harbeths are world class speakers, but they got sold and I never looked back. The sound of a well designed single driver can be addictive.

YMMV, of course.
single driver speakers have very poor higher frequency sound and cant do bass. That is the price you pay for a bit less comb filtering in the mids.
going on three years with my Omega Speakers. single drivers can dazzle, specially with their tone. you'll certainly give up some frequency. quality vs quantity - what makes you happy?
There is coherency in single driver designs that eliminates quite a bit of IMD due to crossovers. A heated up crossover can cause compression, particularly the bass/midrange crossover, and bring a hard presentation if driven. I personally appreciate the immediacy of full range drivers. Dynamics are less affected and again, as a preference, dynamics are on my list of highly desirable characteristics. 
I guess one can tell I like to crank it!
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@dentdog-    Intermodulation distortion is caused by drivers, trying to reproduce too many frequencies, at one time.     NOT, "...due to crossovers."       Dynamic/power compression is another subject altogether; again, not caused by the crossover, but- by overloaded drivers.
For clarity: make that last sentence, "Compression (whether dynamic or power) is another subject altogether; again, not caused by the crossover, but- by overdriven/overloaded drivers."
Mark Audio makes some nice full range speakers.  The large metal drivers can suffer from cone brealup, but the paper ones not so much.  The Alpair 7 metal-cone driver in a "Pensil" MLTL enclosure can be quite musically satisfying.  Don't expect room-filling loud listening levels.  But in nearfield applications, say within 6 feet or so of the speakers with the speakers about 5 feet apart works very well.  Sharp dynamics, great image and soundstage, [obviously] great timing and coherence.  

So, yes.  Full range single drive systems can be quite good.  
There appears to be confusion between full range single driver speakers versus Coaxial / dual-concentric driver speakers.

Tannoy is dual concentric and Kef employs a coincident driver. Both are examples of Coaxial speakers and both (examples given above) employ crossovers.
I've never heard a full range single driver speaker, what's a good example of one for the OP to consider? It would need to produce listenable sound from 20hz to 20khz. Reasonable SPL and low distortion. 
I'm interested in Cube Audio's cheating version.  Full range with subs with an 80/100Hz crossover.  I might build a version of it for myself.  You can buy the drivers and put them in a sealed box for under $5500 total cost.  Then I'd use the 2 x 12" cabinets from my Coincident PREs for the lowest registers.  Maybe you lose a bit of the magic of the full range driver by incorporating that crossover, but you also get full extension that way... and no crossover in the most important regions. 
Build them with Hypex plate amps and use DSP crossovers you won't lose any magic just gain a better speaker.
I have to agree with larryi2 on the Charney Audio Horns. Throw out every conventional negative knock about fullrange single driver speakers. Charney Audio horns are designed on the tractrix theory and deliver music that emotionally engage the listener. It’s all there, natural highs, enticing midrange, and proper well defined bass.

Not all single drivers are made the same "the better the driver the better the performance". This is true with a properly designed and implemented enclosure. I was very impressed with the inexpensive Lii Audio Fast 8 in the Maestro cabinet designed for smallish rooms. Voxativ drivers shine and AER are absolutely sublime! Detailed, fast, and accurate when mated with high quality electronics.

Full disclosure I own a pair of Charney Companion Horns designed for the Omega RS7 driver. Listening to them as I write this. I have owned a number of Omega speakers in the past. Louis does a great job and is an awesome guy to work with. But IMHO the Charney Audio Horns take the RS7 to a much higher level!  Hoping to upgrade to a Companion with Voxativ drivers soon.

Read about Charney and the tractrix theory here:
At RMAF there is a guy who always sets up in the lobby area, and uses Voxativ driver based speakers. He doesn’t play them loudly, but I remember thinking- I’ll be damned if that doesn’t sound EXACTLY like a piano. Every time I went by, same impression- it was like there was a piano player behind him.
I don’t know that this would translate into a fully satisfying experience at louder volumes with other instruments, but man it was convincing for what it was.
@james_edward  +1

I remember thinking- I’ll be damned if that doesn’t sound EXACTLY like a piano.

For a very reasonable cost the Omega speakers (Especially those utilizing the Alnico magnet)  consistently received high praise for their natural sound quality.

Moving to a higher price point the Cube Audio Nenuphar has  been bestowed with excellent reviews by professional writers and outstanding owner feedback testimony. It could quite possibly be the pinnacle of upper tier single driver speakers,. Purity and convincing realism are repeatedly cited.
I recently rebuilt a pair of Ohm Walsh F single driver, no crossover-full range speakers. Favorite speaker by far out of the many I have listened to though I don't have much experience with super high end stuff. Seems like one would classify it as full-range as it is a single cone with single magnet. Plays frighteningly low with crystalline highs (or whatever descriptive crap you want to use). Soundstage is deeper and revealing to the point where it seems almost like a disney illusion. 
Of course only sounds really good when 6 feet into the room so can only listen when my wife is gone (which isn't much these days).
For fun I bought a pair of Audio Nirvana Classic 8 Neodynium drivers and built the recommended enclosure for them. A pretty simple project that yielded results that were much better than I expected. I listen to them quite often when I'm working in my shop and power them with a pair of Pass ACA amps that I built. I was once a single driver skeptic, but not any more.
Great thread.  I'm looking forward to hearing about more user experiences with different brands/approaches.
Evolution and progression does occur.  Someone's experience with a Lowther single driver speaker has little to do with hearing a Nenuphar or Charney. Faulty extrapolation. 
I think you'd be better off with a Woofer-Assisted Wide Band (WAWB). 

It's like a full range, but with a woofer added.  One driver handles 300Hz to 20 kHz.  The big advantage is the crossover stays out of all the delicate areas, and from 300Hz upwards you have a point source.  Obviously plenty of cons to this as well.

I suggest if you want to try this out look into a Madisound kit.  They even h ave them for desktops.


I recall hearing a very well implemented single driver speaker based on an 8 " Fostex driver at RMAF a few years ago. I was really taken with the sound quality. One of the better rooms of the entire show.

There are some inevitable tradeoffs but this applies to "any" type of speaker. Multi driver/Multi crossover speakers have their own set of tradeoffs. It is always a choice of what compromises can you willingly tolerate long term and be happy.
I see Charney claims 20hz-20khz with no roll off on the top of the line speaker. Some of the others in the 30's to 20khz . I see no measurements on their site to substantiate this. I don't suppose there are any third party measurements anywhere? 

I've heard a lot of wide-band/full range drivers used very successfully in multiway systems.  Some were, as you discuss, assisted by a woofer, others were assisted by a tweeter (most commonly with large diameter full range drivers) and some with both a woofer and tweeter.  Most of these were custom-built systems.  An example of use of extended range drivers in multi-way systems includes the SoundKaos Model 42.  By using simple, first order crossovers and allowing the crossover points to be away from the critical midrange, fullrange drivers minimize the negative aspects of multi-way designs. 

“I don't suppose there are any third party measurements anywhere?”

You’re unlikely to find third party measurements cause speakers like Charney are outside the scope of CFO (Chief Fun Officer) at ASR 😂
They would happily measure them  if anyone wanted to send them or if the company did. They are interesting looking. 
There is also a YouTube guy, Erin's Audio Corner,  I bet he would like to put one on his new Klippel.
Indeed, single driver sound is highly subjective, and it's also extremely dependent on the actual build. Among my audio friends' circles we have several single driver speakers which are phenomenal speakers. Bruce Edgar's Lowther horn comes to my mind (RIP Bruce Edgar! He just passed away...), 100+dB/Wm efficiency, and had enough bass and high frequency extension to create the most memorable Cantata Domino experience I ever had. (It has full size chorus and church organ.) My Fostex Voigt pipe could reach down to 30s, and surprised me with the most lifelike timpani reproduction I ever heard, from any speaker. Although Bruce Edgars legendary designs are well known, but not sure whether you can buy any... my Voigt pipe is certainly one of a kind... the commercial Rethms comes to my mind, but that, in comparison completely lacks bass. 
The most important consideration is that single driver speakers have NO CROSSOVER, and will give you the purest sound ever. That is, they will allow system weaknesses to pop up their heads that you had no idea there were. Generally, solid state amps are a terrible match for single driver speakers (although there are exceptions - Michael Yee amps sound great with them.) Also, they are EXTREMELY sensitive to you room acoustics and speakers placement, and it can easily take a year until you find their optimal position. However, if everything jives, you have an endgame situation. My Voigt pipe gave virtually identical experience with recorded jazz as a live jazz event - I listened to my friend's concert at the Dragon Upstairs (in critical listeners mode), and right afterwards put on the Jazz at the Pawnshop, and with closed eyes I did not get any hints which was the live, and which was playback... But that was after 15 years of playing around with them, and when I moved to my new place, I could never set them up so they image like that, and their midbass is not coming to life either. So, YMMV tremendously. They have almost infinite potential, but everything has to line up. If you want plug & play, look elsewhere, they are very long game speakers... provided you find the right one. If you can get an Edgar horn, go for it, although to my knowledge he designed that Lowther horn for my friend, and that might have been the only one he built. I have heard extremely disappointing reports from my friends when they ran into commercial single driver designs.  Good luck!  
Long game is fine if it is not too long and frustrating. Why are they more sensitive to room acoustics than other designs ?
Sound purity, that's worth pursuing.
Single drivers are great....
....70+ years ago.

Things have changed quite awhile's harder to pull off the 'hat trick' to make things blend properly, but....

'One trick pony's' still only do one trick.
Zu make full range single driver speakers.
I have a pair of the Soul Superflys and they sound really good to me. They can be a bit finicky to set up properly as mentioned above but that’s part of the fun, right?

Their high efficiency means a lot of low powered tube amps become a viable option to audition.Zu also suggests some SS amps that pair well with their speakers.

A Miniwatt N3 for example, has more than enough power to make the Zu's sing and go to ear-splitting sound levels. Pretty much any vintage receiver works great too.