Single driver speakers - opinions

1.Design - what is IYO the best design and why?
2.Sound - How would you describe the sound in comparison to other speaker designs?
3.Amplification - what works and what doesn't?
4.Is the WAF stopping your from moving in that direction?
What do you like or dislike about SD spks?
DIY v.s Commercial designs - Pros and Cons.

Feel free to express yourself and your thoughts about the Single Driver design speakers in this thread.

Ideas, your projects, pics, experiances are all fun and welcome.

From my experiance with at least two SD commercial design that actually worked like a charm, I have to say that I am seriously concidering it as my next DIY project.

Awesome speakers when done right.

IMHO, They only do simple acoustic music well. Ask them to do anything with weight,bass or complex passages and they poop out. Plus, all but the best have a tilt in the upper mids that I can't deal with. One driver just can't do it all. It's a music preference thing. Like I said, if you like girl w/guitar or small string stuff then they're great! This is only an opinion and that's all.Take with with a grain of salt. However, I can remember a time when I thought single drivers were the only game in town. Audio is a journey and we sometimes fall for something different and not always better.
I (finally) found a variation on the single-driver concept that sounds great to me. Check out the Hawthorne Audio site. Great folks, wonderful product. This uses, as I understand it, a "pro" driver concentric design. A tad "rolled" on top, none of that hideous tilt in the upper range which every other single driver speaker I tried displayed. I have tried Omega, Hornshoppe. Both fell apart for me other than the "speed" criteria. Both had me wondering what the hell others like about them because the tonality seems all wrong to me. I think they actually "ring" at some frequencies. Listen to the Hawthorne. It is easy to appreciate, getting you into the performance, and the price is more than fair.
If you want a full range and ability to be dynamic with very good response at extremes. You will need to look into very costly full ranges. Some will need large BLHs to produce low bass. These can sound very good not limiting as some think. Many try the wee cheap drivers then find them lacking. You get what you pay for in transducers cheaping out will always sound cheap. Your asking for a driver to do it all and this requires great cost to be done right. Sure this depends what your expectations ar some like the 3-6in afordable full ranges but seems the above 2 poster might not;) I do know of 2 Full ranges that don't need massive BLH for bass. These are Fostex f200a, SEAS exotic. F200a does best in large ported cabs. SEAS in AS about BBC monitor size. Full range benefits point source, phase time correct no crossover. Once you hear a proper designed full range driver loudspeaker with quality drivers you understand why folks who own such like them so.
Serious limitations with SDs, as others have noted. Fine for noncritical low level listening, in other words, background music. Certainly, they have their plusses, but looking at the big picture, they don't cover much ground. Unless there's some sort of equalization applied, they'll always have some anomalies in the frequency response linearity, and unless that EQ is applied before amplification, you've lost most of the benefit of an SD.
Single driver is great in theory, but doing it right is hard and usually too expensive to have mass appeal.

For example, I am most familiar with the Ohm line. Over the years, Ohm has been very successful in delivering very good designs that leverage highly omnidirectional single driver technology to various extents in a cost effective manner.

The Ohm F and A of years past are legends in this category.

The newer Walsh CLS designs from Ohm have built on this approach using a similar but different wide range driver that covers most of the frequency range that most people can hear, but uses a separate phase aligned super tweeter for the very top end.

If there were a true single driver speaker out there that did it all in a reasonably compact design for a price I could afford, I would be very interested.
Would you mention the two commercial designs that you liked?
I suggest you investigate older designs such as Hartley/Lowther etc. - old whizzer cone designs or stuff used in car audio. Don't expect great linearity and bear in mind you will be forced to compromise between high levels of distortion/ringing/breakup/linearity but you can definitely achieve something that will be as good if not better than many audiophile have lots of fun!

One option would be to use the emminence bass guitar woofer - in fact some of you may recognize this as it is modified for use in a well known audiophile speaker. If you stick in a phase plug then you can probably get this to cover 40 Hz to 12 Khz really quite well (on axis - off axis will probably be a nightmare) and at impressive SPL levels (without a phase plug then I think it will roll off around 6 to 9 Khz - still usable).

Good luck and remember that in DIY it is safer to emulate a proven design rather than try to break a new path (unless you are a masochist!!).
If you really want to go first class, seriously, get in touch with Johnk. He uses fantastic parts quality and he has experience with a wider range of fullrange drivers than anyone I know, and is highly competent in enclosures that get the most out of a widerange driver. I have never seen one of his speakers up for sale - maybe it happens, but very seldom.

Or if you want to DIY, then scour the internet for Johnk's comments on fullrange drivers and use what he uses... you won't have his enclosure designs but you'll have a good starting point.

I used to make an "augmented fullrange driver" system, with a helper woofer on the bottom and a supertweeter on top. This is because I wanted to stay below the price range dictated by a fullrange driver and cabinet combinations that are worthy of the name, and besides it would probably take me years to learn how to coax sufficient bass out of a fullrange driver.

I'm not saying there aren't other good fullrange driver speaker manufacturers out there besides Johnk; there certainly are. Names that come to mind are Omega, Hornshoppe, Maxxhorn, Cain & Cain (now Lovecraft), Tonian Labs (mostly augmented by a supertweet), Rethm, and no doubt others that I can't think of offhand. Heck, it could probably be argued that SoundLab electrostats are technically a "single fullrange driver"... but that's probably not what you had in mind!

Give Johnk a holler. He's not as well known as some of the other guys out there, but do not let that hold you back. He is an artisan who does world-class work for a very reasonable price and we're lucky to have him participating here. He has the expertise to be able to do custom designs for his customers without killing you on the cost. Doing that would take me so long that it could never be cost-effective, but John is extremely fluent in loudspeaker system design, multi-way as well as single-driver.

1.Jean Hiraga in his new speaker prototype, using lagendary -
Great Plains Audio's coaxial Altec Company (reissued)15" woofer and 1.75" compression driver in horn-loaded enclousure.
Drivers are not cheap but not expensive either. Seems to generate quite a buzz in audio industry.
2. Not 100% single driver but......
Rethm Saadhana, using custom Lowther DX 55 driver in horn-loader enclousure. Seperate build-in amp is powering 2 peerless custom 6" drivers responsable for bass duties in each speaker.
From what I have heard - I could live with this design.
3.The last but least - Newcomer , CarderSound Madison v2 double horn-loaded design that uses a custom Fostex 8" driver.
Cabinet is similar to Olson-Nagaoka (Sachiko) design and is based on the same principles. From my understanding the cabinet is custom designed with moded Fostex in mind and verious cabinet tweaking was still nessecary to get the desire sound that IMO - was one of the best SD horn designs of lately.

I do agree with most that SD speakers are not for everyone, difficulte to design to sound right and other complaints.
Coloration , sometimes can be not get me wrong....It is the accuracity that we all seek but what if it sounds pretty good??

Far from fanatic or big fan of SD or open baffle designs for that matter however, if done right - it is very interesting concept ( at least for me it is).

- you are on to something with The Masochist guess.
In fact, plans are being made to use some very strange ideas for my DIY projects. hahahahah.
If it won't work.....(and it probably will not) , I will stick with ready & proven design.

Oh yes,
thanks to all.
Duke & JohnK
you are quite knowlodgble and all I can do is look up to you and pick your sneaky, dark, foxy ways.hahaha.

The Carder Sound design has caught my eye as reasonably practical (though still very big/tall) and potentially highly effective in delivering the most satisfying sound from a single conventional full range driver at reasonable cost. I would consider these if/when I have room for another pair of larger full range speaks.

In terms of the best single driver design to work from that I've heard of (meaning fewest limitations overall) I'd say the Walsh driver design concept found in many Ohms and the larger (and expensive)German Physiks speakers (DDD) is the best.
Here's a resource discussing DIY Walsh designs:

I've read some things on the web published by ebay member Mamboni as well that seems to provide practical guidelines for constructing a DIY Walsh speaker.
I have owned many speakers of all ilks and am now really enjoying a pair of Lamhorn's (AER MK-1's with likely upgrade to AER MD3b's) with OTL amps (Tenor)....a very simple and direct system that I can listen to for hours. As others have mentioned, and as is the case with all designs, there are compromises and limitations but in my system and in my room and based on my tastes these speakers/drivers represent an excellent set of compromises where the considerable strengths (tonality, immediacy, resolution, staging and imaging) significantly outweigh the disadvantages which are largely represented by the lack of the lower two octaves.
Stereophile reviewed Fujitsu-Ten Eclipse TD712z single speaker design with 40Hz-20kHz @ -10dB and 70W max power. Sound was - quote:

"As I played a variety of CDs and LPs, the system with the Eclipses had a clarity, transparency, resolution, timbral accuracy, and specificity of imaging that were simply breathtaking."
The Fujitsu look very cool. They remind me of the larger Cabasse's I've seen but not heard.

Are they related in design?
Cabasse are round while Fujitsu are oval/egg shape. Cabasse is a multi driver design. Cabasse is Swiss and Fujitsu is Japanese. They are not related in design, I think, but shape is pretty similar.
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I don't have experience with electrostatic speakers but, if my memory serves me right, they have poor bass extension, less than perfect dynamics and narrow/small sweet spot not to mention large size. Don't they have, being bipolar speakers, to be positioned far away from back wall?
although i am partial to panel speakers, i can't see how one can generalize and say one design is categorically better than other.

it comes down to preference. i find many panel speakers properly set up have smaller deviations in frequency response, within their range, than other speakers.

the criticisms of panels speakers are notorius, but i am willing to accept the comprimises to attain the benefits, which many audiophiles are aware of.
If you haven't done so already I suggest checking audiocircle. Single driver speakers are discussed regularly by many devotees over there.

I agree that no end speaker design is best.

However I would arguably of course assert that a single Walsh driver or perhaps it's descendant, the DDD driver, invented by Lincoln Walsh back in the 60's and tweaked by companies like Ohm and German Physiks over the years, is capable of doing more things that make for good sound reproduction well and has the fewest inherent physical limitations of any single driver design that one might design a (comparable sized) speaker system around.

Mrtennis, Timrhu & Viridian

Full range electrostatic speakers, definitely qualify as the "SD" design. The only reservation IMO (nothing is perfect) is:
*Size - full range electrostats requires large panels
*Require power - most (not all) will need some serious power to make them sound their best. SET, low power tube amps or SS Class A (in most cases) are unfortunately , incomparable with power hungry Stats or Planers.
* room size - I think that we all agree......they need some room to breath.
*Placement - well that is a given with any design, but they might need a little more attention then other designs (not a big deal if you have the space).
* If I had the necessary brainer. (SoundLabs, Quads or new ML would be on my short list.......oh yea, also custom Sanders-all stats, no sub. I am sure that Roger would not disappoint and do his best to please his customers).

Mapman , Kijanki

AC is great source for OB and SD reading.
However for newbie DIY guy like my self it is not enough.
I like to explore every possible angle of design (not this site though) , opinions, plans etc.

It wasn't my intention when starting this thread.

Getting DIY-ers, users, anty-SD design guys to share and maybe educate the rest of AgoN members & visitors - is the main purpose for this thread.

There are pros and cons to every design.
Single Driver speakers are no different.
However, it should not be overlooked while searching for the pair of speakers. It is almost impossible for most audiophiles (or those starting getting their feet wet in this hobby) to audition SD speakers.
By starting this topic, I am hoping that it will at least touch the bases and qualities of this speaker design.
We all learn something new everyday.......and I will be happy to absorb as much info, tips and personal experiences of others to draw my own conclusions that will help me to better understand the art of SD design and possibly become a better listener.

Enjoying DIY projects, SD seems like the perfect "long Winter nights" shop time.

One more thing:

for those on the small budget - if you are seeking the close to state of the art audio on the cheap....look no farther. Even if you can not build your own boxes, plans are widely available. Any cabinet shop will be able to help you with this project. The results may shock you.

Enjoy the music

Mariusz - every design has some positives and negatives. Electrostatic panels are often problems in places with very high humidity and a lot of insects (high voltage attracts them). I don't mean to criticize electrostatic speakers - just to show that every design has some negatives.

Single driver design for DIY might be not the best choice - it is difficult and drivers are not available. Fujitsu Eclipse I mentioned contains just one 4.7" driver and costs $7000.
I'm expecting someone to challenge my assertion regarding the Walsh driver?

For example, typically, they are not an easy load to drive. For the most demanding applications, tube amps need not apply.
Of caurse I agree with you about the shortcoming in many speaker designs (electrostatics are no exception) and I have state that in one of my previous posts.

As to your DIY assessment -
"Single driver design for DIY might be not the best choice - it is difficult and drivers are not available".

I do not really agree with that statement.
Fostex drivers are easily obtainable, as well as Great Plains Audio, Lowther ets.
Fostex being one of the best when it comes to value and Lowther drivers as the state of the art ( some claim their superiority) but costly alternatives.

If you decided to build SD enclosures yourself, it would cost you 10X less then commercial products. Even if you had to hire a cabinet maker or handy finishing carpenter it would still be substantially less then anything close in performance vs cost on the market today.

(you can alway find the way if you put your mind to it)

$7000 Fujitsu Eclipse is a very nice speaker. I had a pleasure of auditioning those on few occasions. Awesome image, soundstage, well balanced, cute bass*.....
*and that is the problem I had with this particular speakers.
Also, 7K is a bit much for what you get from these small monitors. They sure look nice though.

If I told you that:
you can have a speaker that will require some sweat, work, will sound IMO better then those 7K monitors (and many others in that price range) for ........lets say, $1500 - would you believe me????

The trade off - size, look, some research ( not a trade off if you can learn a thing or two about speaker design in general) and low WAF.

What you can get is:
* satisfaction ( you build it....right?)
* open window between you and performers.
* most require just a few watts of power (quality over quantity is the general rule here)

DIY can be fun.

It doesn't have to be hard. Start with an old existing design that you can pick up cheap and try just upgrading drivers, etc. This can make a big difference.

I do not have time for major DIY work. I did do a DIY bass driver upgrade with very minor cabinet and internal damping mods for $130 to my 30 year old Ohm Ls using new high quality Morel woofers. THe results were definitely a big step forward. These speaks sound very good now on most genres even in very large rooms. They are not as smooth still as my professionally designed models, but compete far better than I had really expected prior.
Guys with know how and experience..........please.

What drivers are IYO good candidates for "Single Driver" design? (and could you explain why?)

Good, better , best?


Mapman is right , if you have some spare time and basic tools - it can also be fun and productive.

I have talk to my brother (a cabinetmaker) about various building techniques and options. My conclusion is this:
*It can be done in two ways (both will work though)

1. low cost , unattractive, with simple joinery/glue up tech., 90% of the performance of the second approach (give that the plans are the same).

2. Higher cost, complicated building techniques, precision = higher fabrication costs, longer assembly time,
higher WAF, custom finish, in all - well , quality = time and $$$.

In about 15 min. we came out with the cost of the project, design tech. that will be superior in long term use, build quality, materials and finish options.
In order to meet my high standards , extra budget was dedicated for pro. finisher (solid color) and/or quite expensive veneering process (commercial press).
Veneering with plain adhesive (old school with roller)is a short term solution and will show in the form of "bubbles" and edge wear.

So the choice is yours.
Whichever way you choose, it can be done.
The cost and look is up to you.

Happy listening


You would laugh if I told you what I use and would never even bother trying it if I did.
For me, the most practical "single driver" design is a standard cabinet and full range from 40hz-5-8,000hz with a supertweeter above that. Better than adding the sub, or sub and S-T, or horn, or OB designs.

Transmission line is also a possibility if you want more bass.
Lowest string of the bass is E=44Hz. Grand piano's A=27Hz is seldom used. I will settle for 50Hz. On the high end - I probably cannot hear above 14kHz. Maybe I should go for single driver design.

Only one question to all DIY guys - why Revel bought so expensive test equipment (laser diffraction included) that other companies cannot even afford it? It is much, much more complicated than carpenter's work and veneering with the roller. As for the fun - I am all for the fun.
Thankfully, I was able to listen to the CarderSound with Mariusz (great to finally meet you!) a few nights ago, and was more than impressed with the performance of the two models we got to listen to. Each model had, with the medium sized TyBone model possessing the type of resolution and imaging that would impress the most jaded of audiophiles, while largest Madison offering the type of low frequency performance that I was beginning to wonder if I would ever hear in this design. I never thought bass was impossible, as there are plenty of ported loudspeakers with 8" drivers in far smaller cabinets, so why not a backloaded horn? I'd just not come across it up until now.

I've been around other single driver loudspeakers, and there is a surprising variance in their sonic signatures. My recommendation is that one should carefully investigate the field should they be interested in pursuing this type of product. Yes, they are that different.
"I probably cannot hear above 14kHz"

Good point Kijanki.

I've tested + neither can I for the most part.

I used to though with the same test recording when younger though and on a much less expensive system.

I suspect few past their 30's really can.

So in reality, single driver designs that do not cover the extreme high end but cover the low end satisfactorily is a very practical solution for many more than might be expected, I believe.

I can hear the tweeter supplementing the Walsh driver on my Ohms when on axis, so I would not fore go it in the case of the Ohm Walshes.
Hello Joe (Trelja)

The pleasure was all mine.
Meeting you in person was something I planed on for quite some time now. You are in fact a stand up guy and passionate audiophile. Besides, I like someone who speak his mind with out reservations and sugar coating.
(please say hello to your other half and beautiful little princess. :))

As to experience with SD CarderSound speakers, yes they sure are more then meets the eye. Sound wise - I would definitely be proud to have this sound quality in my own system. Bass was more the satisfying, soundstage was first class on TyBones. Madison, excel in bass reproduction but expecting the same image and soundstage from 8" driver as the TyBone's 4 1/4"-er is simply impossible. Both awesome speaker.

I have express my concerns with this kind of design.
No, it has nothing to do with they way they sound.
It is the size and WAF, which for some may or may not be an issue.

Hearing Jeff's speakers for the second time made me curious about the possibilities of this approach (SD double horn design).
So much , that I am more then anxious to build the similar speakers for my own pleasures.

There are some issues that I would like to point out to Jeff and I will do that will hopefully make his life a long run.

The enclosures are definitely not difficult (but can be) to build but as the product that will have to satisfy all but the most discriminating customers, there is room for improvements (build, tech, appearance wise - sound wise there are no issues).

Ones again pleasure to meet you Joe and congrats to Jeff for wonderful speakers - Bravo.


Kijanki & Mapman

Measurements and state of the art equipment is more then welcome for big name companies, and I hope it will reflect in the quality and sound of the END product.

But keep in mind that all of the expenses are pass on to YOU - the client.

That is why the Revel top models will never be priced to meet the budget of regular JOE. It does make perfects sense though if one wants a ready product with good resell value and second to non cosmetics.

I have never imply that DIY speakers can shamed top speaker designs (commercially available).

What can be achieved , is the very close to live music reproduction that can make you stop looking for more.
Take all the benefits of SD design and possibility of do it it yourself (if your are persistent enough) and it is IMO no brainer. Just imagine the saving, performance and smile on your face .....knowing , what would cost you if you were going to find that kind of sound - in commercial designs.

I am not saying it is THE WAY, just something to think about or just another alternative.

I have had some very well known brands in my system (costing thousands of $) and I am telling you - I would be more then happy with SD speakers that are well design.

There are many SD speakers widely available form respected sources if DIY is not appealing to you. Auditioning quite a few, let me to believe that it is possible to build one with minimum trade offs. But keep in mind , NOT ALL are as good as the ones I have mentioned (YMMV) and there is plenty more that I have not heard yet.

So if you, or anyone for that matter is interested in this design - I would suggest some reading and most important - audition, audition, audition.
It is the only way to tell , if it is what you seek - MUSIC.

I can use the same types of test equipment as the large manufacters. Its realy not a issue. This gear is available at a fair price. I use UVW test facilitys and Madisound plus my own. Still what matters is sound quality in home. And you can test all you want wont tell you much about the sound quality in room unless somethings amiss.
Mrjsark. I have used small BLHs from Johnk and the later upgraded to a Madison (double mouthed BLH) from Carder sound. I’ll never ever go back to a multi-driver speaker again.

I use low(ish) powered SET/SEP amplifiers, and the benign impedance curve that a single driver presents allows my amplifiers to work at their very best. The sound is totally effortless and dynamic; I really get the feeling that the amplifiers are idling even at high volume levels.

The dynamic quality and speed of a single driver is so addictive that a multi-driver speaker simply puts me to sleep.

Sound staging is out of this world. The double mouthed horn of the Cardersound throws a huge soundstage, not unlike what I experience at the opera, yet it can be very intimate and gentle as a recital.

I see a few post that make stereotypical (excuse the pun) criticism of single driver speakers, but they are all pure ignorance. I think if anything, it’s a matter of taste. We simply don’t all appreciate or like the same things.

I think your comment, “awesome speakers when done right” is spot on.

Thanks Paul,

and You are right on the money. Speed, soundstage, effortless presentation and accurate portray of "emotions" surrounding particulare recording.

There is definitely something seductive about "Single Driver"
speakers to be sure. Are they perfect? :) Nothing is.
You guys can help me out with my next statement.......

IMO, it takes a bit of growing-up, seasoning if you will -
to appreciate the qualities of horns & single-driver speakers.
I feel the same way about SET amps or tubes in general.
Even though I am relatively young, my understanding of music and the way it should be portray by speakers and associated gear is plain & simple. There are planty of speakers and electronics that sound good or great. But I am sure that "good or great" in most cases is usualy not enough.....I hope I could speak for most of us......obviously I can not, so let me place IMO - just in case someone disagree with that statment.

To get back to your post Paul,
yes - SET amp (Joe's Consonance Cyber 211 mono-blocks) sounded way better with CarderSound then SQ integrated (tube, moded) and my own RWA Sig.30.2 t-amp , which we brought that day for audition.

I would also think that good OTL amp might be another alternative with potential to do those speakers justice.

I personaly had very high hopes for RWA amp but it simply prove to be poor match (it worked great with Rethm Saadhanas though). I also brought Isabella (RWA) preamp which did not disappoint - to bad we haven't had a chance to use its build-in DAC and swap some tubes (Amperex BBoys and Mullards that I had in my car).I am sure that with little tweaking we could have raise its performence few bars higher.

you are one lucky man to own Madisons, have the room to do them justice and angel for a wife :)


You have to live with single driver for a while. Then listen to multi-way to appreciate the degradation in sound.
Also I am not getting any H-F boost. That is more a characteristic of high efficiency single driver.
A small room is helpful to boost the bass.
I would not go over 4" as they become too directional when larger than that IMHO.
Yeap, 4incher image like no other but there is a trade-off.......Bass & dynamics. Unfortunatly you have to pick your poison. Rethem Saadhana, sort of figure it out by useing 6inch custom Lowther DX55 and added two 6" peerless drivers for bass below 70Hz or 100Hz (if memory serves me right).
As I recall, the image was excelent and sweet spot wide enough for avarage listener.
The single driver originality was a bit banded in this particulare exemple but it worked like a charm.

Mariusz - I checked Lowther website and found that EX series speakers go as high as $2k a piece. Some of designs they show use 2 speakers per box = $8k in speakers alone (I like to have the best). One of the titles of their FAQ is "Why bass refleks is the best". Now I'm not sure I should trust them. According to Andrew Lipinski (Lipinski 707 is A class in Stereophile) bass refleks is th worst possible choice because of coloration.
So far no-one has mentioned PHY or Fertin, both from France. These drivers are arguably the cream of the crop in high efficiency 'full range' drivers. The PHY is featured in the Ocellia loudspeaker, one of the few that can really get down to 40Hz (but not cheap by any means). Tonian Labs imports PHY and uses them in their speakers as well.

Both drivers feature Alnico magnet structures, exotic diaphragm materials and substantial basket construction. Various means of high frequency extension are also available including a peizo tweeter that uses no crossover

Being available in 16 ohms (or more in the case of the Fertin) they can be easily driven by any amplifier technology, although the discerning listener will notice that amplifiers with a high output impedance will sound better on them (Better: smoother, more definition and more impact in the bass region).
I have met Andrzej (Andrew) Lipinski (my Countryman,but away)
and truely admired his enthusiasm. His experience is oriented more about the accuracity and studio application though.
If you like his speakers.......just ask. I might be able to present you with an offer you won't be able to refuse.

But seriously,
Lowther drivers are in fact very, very expensive. Are they worth the extra money, I will leave it to you.

Double horn design (just like CarderSound) will work with these drivers as well. You might have to "tweak" the box a little but it can be done.

I would also like to find out if Lowther drivers could take this design even farther. However, from DIY-er point of view - keeping the value within the reasons is my main concern.
If you decide to go DIY road, remember that Fostex as well as Lowther drivers keep their value on used market. Even the well desgn boxes could probably find a happy home in case you deside to move on in different direction.
To be quite honest, I do not see the need to upgrade from Fostex to more expensive Lowthers. From what I have heard, you will be more then satisfy.

thank you for your recommendations (it rings the bell) and I will look a little closer at those drivers.

I have heard a lot of positive comments about your horns too.
A bit pricey but you get what you paid for....I guess.

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Mariusz - he is my countryman as well but he operates in Massachusetts and it is not walking distance from where I am. I will take you on this offer - didn't you say 75% discount?
'Brines Acoustics' use the Fostex 8" F200a (as well as other cones) in his SD speakers. The F200a is a seriously good cone.
The prices are very reasonable. You can buy them fully made or in kit form.
I would like to hear a pair of his speakers.
I get confused with S-D phase angles but even S-D apparently change phase.
Here is one Jordan JX-92 so I don't know if they are as good as they claim.

What effect does this have on the sound/ Maybe Atmasphere will know.

Also people have noted that a ported S-D will not be coherent as the port is also out of phase. I don't know if this is true or not either.
Here are a couple of examples of small driver but still reasonable bass if volume is not too loud:

Sampan FTL
The 4in are not even close to quality 8in drivers in performance. If they where I wouldnt offer a 8in full range only 4in. The 4in drivers are very limiting the 8in like lowther pm4a dx4 SEAS exotic Fostex f200a fe208esigma, PHY etc all are far far better than any 4in;) And Gawdbless I was the 1st to offer f200a loudspeakers. I worked hard to keep fostex from discontinuing f120a f200a. For 6 years I imported almost all the f200a that came to US. Still offer f200a as a custom built. But the new SEAS drivers a good step up from f200a so this is the 8in full range I offer now.
The F200 by Bob Brines that I heard was very rough in the H-F and also required notch filter for nasty breakup. Any cheap $5.00 tweeter would beat it, IMHO. I would need more clarity to understand how every 4 inch is worse than any 8 inch, except for bass and dynamics, of course.
Take a good 4", use it in a small room, treated with C37 and EnABL'd and you have something very close to "audiophile" quality bass flat into the 40's. Again IMHO. Plus much better dispersion and soundstage than any eight inch. Horses for courses I guess.
I can't comment on the sound quality of 4" cones, I do own though Fostex 6" FE168Sigmas in BLH, as well as the 8" F200a. As I listen to both every day, the F200a is way way better than the 6".IMHO.
Cdc just how many 8in full range designs have you've owned? And slapping a coating on a cheap driver doesn't make it better this kind of so call modded drivers will have reduced performance if one really understands transducer or cone design. Paying so much for a driver that's worse than stock is one of the big rip offs in audio today. More weight on cone might lower bass but would reduce treble, midrange, reduce peak SPL ,driver is now slower. These mods dont address the cheap stamped frames, cheap surrounds, cheap magnets, small cone area that fe126e sports. After all f200a has a massive powerful alnico magnet a milled basket as good as they can get, goes stamped or plastic= cheap, cast or injected metal basket= better, milled from solid block at massive cost but much more stable = the best type, also f200a has far more advanced cone material over fe126e And since its 8in can play much louder and lower, fe126e hits break up far before any 8in, trebles far better on f200a if used with no filter proper cabs, than fe126e. Most any loudspeaker manufacturer or designer can have a transducer company proper mod drivers or build driver as complete custom. Average DIY types using coatings on cheap drivers than pricing such up. Is almost as bad as the polished rocks and magic clocks.. Better to buy a more costly original equipment driver than let any self proclaimed expert muck one up so. So CDC a c37 or enabled 4 1/2in better than f200a, SEAS exotic, PHY ,fe208e sigma fe168e sigma. AER Lowther ya right I got some swamp land for you enabled guys its c37 treated. Ever priced a c37 treated Lowther talk about no resale value. And if such tweaks do make drivers so much better than anything else Fostex or anyone else offers don't you think the transducer designers who brought you banana pulp hyperbolic perabaloadal cones hd surrounds t500amk2,triple Alnico mag t90aex,w300a2, w400a 2, fe206esr or yes even the lowly fe126e would know that a bit of old c37 would so greatly improve fe126e besting all there work....This modded drivers just a way for a schmuck to make a buck...A way for manufactures to offer cheaper drivers while telling everyone there fe126e is so much better than anyone elses thus the cost. And the f200a sounded poor because of its notch filter....You may take this as a attack but its honest advice. I design with most all full ranges as well as many other transducers. c37 been around a long time guys been treating cones for the worse since the 60s. Nothing new. Ive built 6 designs for fe126e alone. And yes Ive heard enabled thus my post. And the wee 4 1/2in do 1 thing better than the larger full ranges of quality they cost far less so if you paid more for c37 you got took. Many who can not afford the good stuff delude themselves into thinking what they purchased is better. Good for the ego but bad for others when this wrong info gets passed about as fact. Face it when most hear wee 4 1/2in full range loudspeakers they dont like them why most of the posts saying full range performance is weak no bass or treble can only play simple music at low volumes are from folks who experienced the small wide bands. I do disagree with them a fe126e can make for a wonderful loudspeaker in its price range. But its not the ford escort that bests the Mercedes super car. Would be great for all in this hobbie if this was true but its not and just saying its true doesn't make it so.
Have to agree with JohnK on this one. I have both Fostex 126E and 206E speakers, and there is no way the 126E gives a better soundstage – granted in my case the 206E is in a much more expensive cabinet but the 206E provides better delicacy, detail, soundstage, bass etc. The 126E is simply outclassed.

John, what is your opinion of Lowther drivers? I am sort of toying with the idea of trying an 8" Lowther (EX4), mostly due to its higher sensitivity and that I can obtain then with a nominal impedance of 15ohm.