In April 89, the French magazine, La Revue du Son, published this review of the newest incarnation of the EA12 panel by AW Audio.
Called the PA12.2, it was a significant improvement on the original model.
What this review reveals though for the first time, is some technical information about the construction of this outstanding speaker.
And I had guessed successfully some of them...(see previous posts on AW Audio)
First, all the full range speakers are in line, 2 on top of the tweeter, and six underneath. The tweeter is described as an inverted dome tweeter: at that period, only Focal was using that arrangement, so we can assume Alain Wacquet was using one...
The full range speakers are mentioned as being 12cm in diameter, and one can assume that these would be of Audax origin.
Although not exactly a D'Appolito arrangement, it certainly have a lot in common with it in terms of imaging and transient response.
The tweeter is working only over 5KHz, and may or may not been time aligned mechanicaly, but certainly in the complex filter, as one main quality of these panels is their transient response.
It seems also that an external filter is used to compensate for the acoustic short circuit in the bass region, inevitable consequence of a dipole speaker. My recollection of these speakers is that the bass spectrum, although not extended very low, was still believeable and extremely clean.
Alain is a jazz enthusiast, and his demos always included fantastic percussions, which always came out of these panels as extraordinarily accurate.
If I can quote Patrick Vercher and Jean Hiraga in their assessment of their performance, they compare these panels to electrostatic panels, the transcription of the music being "luminous", full of micro details, very respectful of instruments timbres.
Again, my own recollection of these speakers is that voices were very realistic, specially female (Sade, very popular at the time, come to mind...) and the lower medium and upper bass region being perfectly reproduced due to the absence of box coloration.
On small jazz formations and live recordings, you could hear the ambience of the venue, and one could easily feel being there - what any speaker designer is trying to achieve with various degrees of success!
A few years later, Alain introduced the short lived "Transparence", probably the best way to describe his creations in one word.
I am hopefully meeting Alain at the Paris Hifi Show next week-end and expect to get more first hand info on these unique speakers.

Today, I will review the two brands/products that have most impressed me in terms of speaker design and new to me.
Atohm and Waterfall Audio are kind of cousins as Thierry Comte is a partner in Waterfall, and the main driver (sic...) behind Atohm.
Besides, Waterfall Audio uses almost exclusively Atohm speakers.
Both companies have created a range of speakers that have some design criteria in common, but have achieved very different products out of some of the same components.
Atohm drivers are all high efficiency and both bass and midrange drivers have a metal membrane. Their top of the range tweeter however has a silk membrane and a 28mm diameter coil small enough to always stay within the humongous magnetic field of more than 17000 Gauss, resulting in a massive 98db/w/m efficiency.

We were exposed to their top model, the GT 3.0, a so-called 3.5 way freestanding speaker beautifully finished and equipped with 2 7inch bass drivers, 1 6inch medium with a phase plug and the above mentioned supertweeter.
The crossover frequencies are 100, 150 and 2500Hz, hence the 3.5 way name.
All filter slopes are 6db and the tweeter is time aligned.
The midrange driver has its own chamber fitted with an internal conical structure aimed at taming the standing waves and reflections inside that cabinet. This is reminiscent of the structure in the B&W Nautilus, but inverted inside the cabinet.
The bass drivers are installed in a bass reflex enclosure with a laminated vent at the base of the speaker's cabinet (like in our Microphase SWS subwoofer, this arrangement removes most of the potential problems linked with the floor structure and the position within the room).
The very well conducted demo showed the accuracy, speed and time alignment of this speaker, highly respecting the timbres of instruments and at 92db efficiency and 300W power capacity, reproducing the music with a realistic level and a total absence of distortion. Definitely in my top five at the show.
Their cost of 7,900 euros + seems to be the norm at that level of quality (Elipson 4260, Vienna Acoustics, or my favourite Martin Logans are twice the price...)

Waterfall Audio has taken a different approach, using some of the same drivers, in their top model, the Niagara.
First of all, Waterfall has made a name for themselves by introducing glass cabinets for their speakers.
We all know that glass is a very inert material, but being transparent, one cannot hide much inside the cabinet. Besides, it is quite a difficult material to process and assemble, more so once you add the complexity of a horn in front of the tweeter!
But Cedric Aubriot and Thierry Combe are not the types to refuse a challenge, and they came up with a number of innovative ideas to make this speaker a "chef d'oeuvre" in the sense of the Compagnons in the Middle Ages.
The result is a beautiful objet with a very high WAF - they have their Export Manager, Nadine, as their first judge, and she has convinced women (and men, I am sure...) in 30 countries to agree with her and buy this wonderful object!
Having said that, the auditive result is totaly in tune with the aesthetics of the product, proving once more that form should follow function if one wants to achieve the best possible results in any field. Electroacoustics are still full of "black magic" and in this case a transparent one: the filter is hidden in the base of the speaker, and so is the larger passive bass driver. Again, the midrange driver has its own enclosure baptised Acoustic Damping Tube, and the bass is generated mainly by a second 7inch driver. The tweeter is a 21mm diameter with a silk cone behind the proprietary glass horn. All drivers are bespoke versions of Atohm drivers.
The sound is solid, accurate and neutral. At 89db and 200w power handling, the output is realistic with a very nice, precise soundstage.
At 27,000 euros, this is not for the faint hearted, but a tenth of the price of a Focal Utopia and a lot easier to fit in one's living room. And with all due respect to Jacques Mahul, a much more lively proposition, more engaging with the source material, and, after a relatively short audition, certainly not less accurate.
It is to be noted here that Len Wallis (of Len Wallis Audio fame in Sydney) has given me access for a full morning to the Utopia in his showroom with two of his most knowledgeable sales people (and vinyl enthusiasts on top...) as my 60th birthday present...and so, my opinion of the Utopia is based on a much longer listening session on my own material. Although we had probably hal a million dollars of equipment in that room, I cannot say I was totally convinced mainly because it was almost surgical and lack the passion to engage my senses totally.
So, if I had a spare 40,000A$, I would certainly consider the Niagara!
I would like to try them with my Bryston amp and a Michell turntable and Grado Signature cartridge. Maybe the Aussie distributor of Waterfall Audio can organise that for me ( I will BYO my amp!!!)