How good are single drivers speakers in reality?

Lisandro_P,













this depends very much on the driver.













Lowthers sound spectacular in backloaded horns (and rumours have it) also in bi-loaded horns like the famous TP-1 enclosure. TME, they wear out sonically with time, the long-term listening fatigue grows in your mind.













Any good paper cone driver will sound stunningly good when run in an open baffle, just take an old door, saw a hole in it, mount the driver, try it out.













I can recommend the Fertin FLB20EX very much, see my post in the high sensitivity driver thread. I listened to it, i bought it immeditately.





Before that and at the moment, i made a long-term listening experiment to see if i could live with such a driver and surprise,surprise, found that i could not live with the mud created by an enclosure anymore. As an intermediate solution, an old Focal 7N303 with a "neoflex" cone and a small tweeter for over 10kHz does a fine job.











But i disgress, you asked for fullrange drivers. There was an article in the German Klang+Ton magazine (3/2000) describing some drivers and showing fancy impedance curves. I could not believe these curves to be true (was the author out there to prove that drivers with whizzer cones are junk anyway?). Consider, if there is a phase shift of >360° (some Lowthers showed 3 times of that) and different parts of the diaphragm are radiating differnt frequencies but are mechanically linked together so a considerable degree, do the whizzer cones wait three periods silent until they radiate, or (more probable :) ) do they get ripped off the main cone then due to the phase shift? They should, according to the curves, but from own experineces with my Lowther, i can tell you they do not.











From own listening experinece i can tell that the Jordan drivers are just fabulous and i would consider some of them as fullrange drivers. The also survived the Klang + Ton article with flawless measuring reputation (no other driver did).











The Diatone driver is wonderful from 80 Hz to 16 kHz , just not so efficient. It is sold for quite some money by EIFL, Japan, it looks like cheap junk an probably is but it is a musical instrument. To get at beginner's level into widerange speakers, this driver would be my recommendation.











The Lowthers (and speakers derived from the lowther like the REPS1 and the German AER drivers) are well-suited for horn use and their frequency response makes them ideally suited for horn use but not for normal use(the horn boosts the low mids and the speaker needs thsi to sound balanced), they sound *speed-of-light* fast and very natural and open and the colour/detail resolution of the upper low end is hard to beat; the lower low end simply does not exist. But i know few folks sticking to Lowthers for longer than a few years, most (including me) sell their Lowthers after a while due to listeing fatigue.

The AER drivers seem to be an exception to some degree, they have no phase plug, the doubleVC is wound outside of the VC former and their diaphragm is softer than the Lowther one. Roumours have it the AER driver has not the typical Lowther "shout" but as tradeoff they lack dynamics and punch over the whole FR. THey certainly have the least longterm listning fatigue of all Lowther-like drivers.







The Jalabert/PHY driver is wide used for fullrange and open baffle applications, i did not hear it myself but my buddy Hartmut, whose preferences are very close to mine, complained about no treble and mids too coloured and PRaT not ok. The open baffle expert i recently consulted uses a PHY and seconds that but says that with himself aging, he more and more cannot stand treble and he loves the PHY's colorations. R.L.Andreoli developed an openbaffle speaker with a PHY and a tweeter of his choice added. I guess this driver is a question of taste like no other driver.











A french friend told me that Supravox is a very good choice if you happen to get a pair of properly manufactured drivers, their 215/2000 has no whizzer cone and can be ordered with an AlNiCo magnet or a field coil motor. Supravox also has an 8"er with whizzer cone and a wider variety of other drivers. Some of them have fancy performance concerning, efficiency, moving mass, freq.response, f_r.





However, as a dyed-in-the-wool engineer and being very quality oriented, i do not second sloppy manufacturing practices (magnets coming off, scratching VCs and the like) and feel urged to warn from Supravox. If you decide to risk this and give them a try, tell them straight you have heard about manufacturing problems from different sides (i bet the folks on the fullrange driver forum and the high efficiency speaker asylum having dealt with Supravox will second my warning) and that you want to know if this is true and what they undertook to get over that and that you will put particular focus on manufacturing quality and that you wold love to report on forums that the rumours are not true and just hot air , something like that , yo 'll find the right words :)











Well, then there is my own choice, the Fertin FLB20EX which sounds neutral on the warm side, very uncoloured but colourful, incredible detail resolution, wide 3D soundstaging (who needs surround :) ) with almost palpable body and heaps of air between sound sources, fantastic treble (in fact the "treble" arises not an issue at all, it is just natural and merges) . Transients are shocking, µdynamics are the best i heard so far. µdynamics, have to dwell on that, the speaker has sweetness and seductiveness unequalled to my experinece so far.


Another funny observation: the speaker sounds like a life act and if i walk ito the other room, it remains to sound like a life act (located in the other room). I had this with no other speaker, walking in anonter room and you have ,clearly audible, unmistakable, canned music playing.


As i wrote in my other post, all my wet dreams have come true. I will report here as soon as my speaker is running.
 
I'm curious, too, so...

...I bought a pair of cheapo RS 1354a 5 1/4" full-rangers and built the simple "Exolinear" box (~45"h x 6"d x 9"w) from the full-range driver forum. The sound is far from perfect, but very listenable I am quite surprised at how boxy my big-rig sounds now. My wife has a few amusing things to say too. Not being an expert, I cannot tell you exactly why but they are very appealing even at my $30 total cost entry level. The sound is certainly lacking the top and bottom of multi-way speakers (my sub helps fill in some of that) but there is a presence and detail that is intriguing.

Sort of puts a dilemma out there - trade technical and tonal perfection for simplicity (and fewer electrical components), presence and space.

Anyway, I'm hooked and looking forward to building a small set of folded horns next. This can be a very inexpensive way to play the hobby and there are still the other extremes in the single-driver world of very expensive drivers and complex box shapes (search for the Hedlund Horns). But it also teaches/forces one to examine what real values are in the spectrum of hi-fi.

Good Luck,

DV
 
dice45:
I find 'Klang + Ton' interesting too, but they some times mix up their pictures, descriptions and measurements, wich can be very confusing.
In the article You're refering to in 'Klang + Ton' they had a go at ACR/Fostex FE 103 Sigma. Have You ever heard them?

Lisandro_P:
I once, back in the eighties, had a pair of fullrange speakers with Fostex FE 164, and I still can't forget their dynamics, and how they made the musician apear in the livingroom, as long as the music wasn't too complex. Mind you, they were only closed boxes. No horn nor BR.
 
Single Driver

After a few years of tweaking mtm style speakers I have done a few single driver speakers w/ good results. Basically it has tought me that a wide and really flat frequency response is not as clear an indicator of good sound as I thought. If you are not familiar with www.melhuish.org I suggest you take a look as it is a very good single driver site with a good forum.


www.melhuish.org
 
Originally posted by Hoffmeyer


dice45:



I find 'Klang + Ton' interesting too, but they some times mix up their pictures, descriptions and measurements, wich can be very confusing.



In the article You're refering to in 'Klang + Ton' they had a go at ACR/Fostex FE 103 Sigma. Have You ever heard them?







Lisandro_P:



I once, back in the eighties, had a pair of fullrange speakers with Fostex FE 164, and I still can't forget their dynamics, and how they made the musician apear in the livingroom, as long as the music wasn't too complex. Mind you, they were only closed boxes. No horn nor BR.






oops, folks, forgot the Fostex completely, getting senile, what was tha disease name ? Alz.. alz.. alz ... :( cannot remember .... :) but i meet new people everyday





The Fostex FE103Sigma makes wonderful music but its detail resolution left room for wishes. I heard it in a L'Audiophile Petite and know the driver very well. Its Qts of 0.32 is maybe still usable for open baffle use, 0.4 to 0.5 would be better and maybe the lack of detail was due to the enclosure. it is unbelievably dynamic, considered its size.


As soon as my modular baffle system is up, i should try it in an open baffle.




I do not know th FE164 but do know the FE208Sigma. My friend buld a pair of Jericho horns with them and later replaced them by Lowther PM6A which needed no tweeter. In direct comparison, the FE208 needs one. Shocking transients, very smooth and sweet sound, probably way less longterm listening fatigue than with a Lowther.


After all, a very recommended driver.
 
dice45,

Well, one of the things that caught my attention right away were the impedance curves (and the frequency responses, but being full range drivers i knew beforehand they wouldn't be that flat :) ). How does that work mechanically, beats me. But they seem to get raving reviews... so i AM missing something.

Thanks for the FLB20EX recomendation. I'd like to build a pair of small quality speakers to match my JLH 20w in the near future, and single drivers are something i'm considering (perhaps with a small tweeter to help the highs beyond 15khz). Keep me updated on those speakers!
 
Fostex FE168Sigma

I have a pair of these beasties which will be going into my second design of backloaded horn cabinet. I can agree with previous comments about dynamics and imaging.
Have never heard well sorted electrostats so I can't comment but these image better than any other speaker I've had the chance to listen to.

Of the sigma series intended for horn loading, the 168 appears to have the flattest response. On axis it measures +/-3dB from 150Hz out to20kHz and this at 94dB/w. Below 150 it is designed to have the bass reinforced by horn.
The response is flat enough to require no eq.

Off axis, there is a severe rolloff of treble (like 15dB down by 10k if you go 30 degrees off axis!) on axis, no hassles. this means that there is a definite sweet spot that you want to stay in.

A well built, easy to use driver. personally, I like it (and my wallet don't have enough stretch to buy me Lowthers)

drew
 
Re: Mostly full-range

Full-range speakers are a myth... but they can be wonderful.

"OK. What is he talking about"

I am currently running a full-range speaker -- a pair of BD-Pipes using Radio Shack 40-1197s. These drivers aren't the ACRs the design calls for, but these things knocked my socks off. They were subbed in for my ESLs when it came time to re-cap my power-amps. These don't do some of the things the ESLs do, but i find myself listening to the music more so overall they are more satisfying... and now the quest*, if these speakers & the dumpster SE pentode amp i am using now are more enjoyable for less than a 1/10th the cost of the stuff it replaced, what is possible with better drivers, what happens when i build a better amp. But i digress.

* getting there is half the fun -- especially when you are building & exploring

My full-range speaker, like many peoples is really not a full-range speaker. There is a sub. Most people talk about their FR speakers and say, doesn't go deep, but what there is is wonderful... yes you can enjoy the music with little deep bass, take the LS3/5A for instance. But add that sub and wow! So now the full-range doesn't have to handle those big excursions and the mids are even sweeter.

And how many full-range systems add a little help to the top? Many... On my system i listened for weeks and enjoyed it. Then i added a tweeter and tuned the XO till it just about disappeared. You only notice it by disconecting it... it covers from 10-12k up, maybe a little less.

So my full-range speaker system is actually a 3-way, but 100-10k are covered with a single (almost) full-range. The critical mid-range is untouched by XO (although the active XO isn't completely transparent, the gain with it and the subs is greater than the loss from the XO)

And i can use a nice meaty SS amp on the bottom, and a sweet little valve amp on the top... thots of new XOs dance in my head.

ramblin' dave