Single driver speakers - opinions

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

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.

Atmasphere,
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.

Regards
Mariusz