Source: Auralic Vega DAC, Ayre QB-9 DAC. 2011 MacMini, Audirvarna 1.5.10.

Amplifiers: First WATT SIT2 (driving full range and tweeters), Pass Labs XA30.5 (driving woofers).

Preamplifier: Bent Audio Passive fitted with TX102 MKII Transformers.

Electronic Crossover: Pass Labs XVR1. 2nd order at 80 Hertz on the woofers only. Duelund Cast paper in oil capacitors and inductors for 9,000Hertz 2nd order on the tweeters.
The interconnect cables from the preamplifier to the SIT2 are fitted with a Teflon .01 MFD capacitor in-line at the amplifier end to 1st order filter at 150 hertz. Good for the full range drivers.

Cables: I design and build my own interconnects and USB cables. Speaker cables are all Audience AU24 SE. Power cables are all Audience Top of the line.

Power Conditioners: 4 of the Adept Response aR2p-TO.

Audio Rack: 4 Tier Mana Amp Stand.

Room Dimensions: 13’ W X 20’ L X 8’5” H

AC: All dedicated Audio outlets/receptacles.

Reference Speakers: Cabinet is a hybrid bass reflex/Open Baffle. 18-inch wide baffle by 60 inches tall. The reflex bass cabinet is also 18 inches wide by 20 inches high by 37 inches long. The top of this reflex cabinet is curved to avoid reflections.
The drivers are one Altec 15 Ohm 416 woofer, one Lowther Ticonal PM2MKII, RAAL 140-15D Dipole Ribbon tweeter.

Product Under Review: Rullit Atelier AERO-8, 8” field coil full range drivers. Ebay Listed At $5,800 pair.

It has been months since beginning my evaluation process of the Aero-8, Eight Inch Field Coil Full Range Drivers from Atelier Rullit. Why so long? Because these drivers are from a decidedly Boutique design environment, where even the product reviewer is often subjected to less than friendly treatment much of the time. And that is when there is actually two-way communication.

So, I decided to wait and determine if the designer behind the Aero-8’s was simply an arrogant curmudgeon, or just a really bright and talented designer with a bit of a prickly and eccentric personality. In this case “prickly and eccentric” is the best-case scenario and turned out to be what I was dealing with. So, let’s get down to the drivers at hand.

The Rullit Aero-8 is an Eight-inch full range high voltage field coil driver. They sound best between 120-150 volts DC, where they will draw approximately 400 milliamps. Sounds dangerous, but the low amperage makes the occasional accidental careless electrocution harmless. A little electro shock therapy never hurts.

I prefer them at 135 volts where their motor case temperatures reach a steady 130 degrees Fahrenheit. So, if you are one of the minority out there who are already enjoying the company of field coil drivers, then you will likely need a new power supply that reaches well beyond the usual 12-17 volts required by almost all current production field coil drivers. No problem, because building your own VERY GOOD sounding supply for the Aero’s was easy and cheap.

Well, here comes the part where I wish that I could include at least several paragraphs from Mr. Oleg Rullit himself describing the numerous unique attributes that separate his Aero-8’s from the pack and contribute to their (we’ll see) stunning musical performance.
Well, I asked and asked again. I tried explaining the benefit of a designer’s input. Threatened not to post. Then I just gave the hell up.
Below are the two short paragraphs that Oleg DID recently forward to me. I have prefaced Olegs’ response with my last ditch requests for ANY information.

ME:” I NEED for you to give me some information. The kind of stuff that sets your drivers apart from ALL others. I am NOT asking for proprietary information, but I need to include stuff like, what makes your designs unique? What is it about your cone material and maybe their construction that sets them apart from other drivers?”

OLEG: “ sorry, Lance, I can't discuss this subject. I don't want to reveal any detail of the knowledge I've acquired. I was thirteen when I did my first repair on a speaker, and since then thousands of drivers have gone through my hands, and I have tested almost every single one. With the beginning of the 3rd millennium I came across a speaker of German pre-war production that sounded absolutely different from any other I knew, and this was the initial spark for my research. Little by little, step-by-step I've been constructing hundreds of prototypes, without the aid of recipes. I had tried hard to get old documentaries, but without success. The "old school" of German speaker building has become extinct, and I have reanimated and enhanced it.”

ME: “Why did you decide to make Field Coils that require 100-150- volts instead of the currently usual 12 Volt versions available?”

OLEG: “It's no secret that the usage of the 12V version is for profit only. There are hundreds of low voltage laboratory available that don't serve music in any way, especially the field coils have notably less windings, for they are made with thick wire in order to economize working hours.
The usage of high voltage field coils enables to use components of power supply that I selected by ear. The aim is authentic music reproduction, as "live like" as possible.”

The above is the most product description information that I have ever received from Mr. Rullit. But I must admit that it was pretty useful stuff.

These AERO-8 drivers present THE MOST full range response from any so called “full range” driver that I have ever experienced, regardless of cost. I needed to dramatically reduce the output of my powered Altec 416 on board 15” woofers and completely do away with my dual subwoofers. These smallish field coils did not only produce more bass than any other eight inch full range driver tested, they produced deep, rich, powerful and beautifully detailed bass from upper to the lowest bass registers, within reason.

The high frequencies were not quite as impressive (the amount) as the bass had been, but it was so damned natural, with a rare sheen that made cymbals, upper piano registers and airy room acoustics come Alive. Their highs were the sweetest that I have yet encountered from a wide band driver.

None of the above raves would matter much to me if the AERO-8’s would not have offered something special in the midrange. I am continuing to have a very difficult time coming up with descriptions to describe these driver’s unique midrange qualities.

There is a unique type of weight; density, tonal character and life like Aura that made me sit for hours upon hours enjoying music. I have rarely ever spent more than half an hour at a time listening to music lately. I guess that I simply loose interest regardless of the sound quality. It’s just my nature. However, being a midrange aficionado, then I just could not pull myself away from these speakers. There is just more inner detail in their midrange, but with an easy finesse that I am totally unaccustomed to.

Now, I really wanted to get into how the AERO-8’s imaging compares to my reference system described above, However, the cabinet/Baffle types are just too different to make such a comparison relevant. Before I get too deeply into the AERO-8’s imaging capabilities, then I had better point out that my reference system and the fully Open Baffle system housing the AERO-8’s incorporate the EXACT same driver and crossover compliment. Yes, I have duplicate Altec 416 woofers and RAAL 140-15D Dipole tweeters for quick speaker system comparison purposes.

But, The AERO’s are housed in my reference fully Open Baffle system. This baffle is 24” wide by 47” tall. The full range driver resides centered 32” from the floor, the big RAAL dipole tweeters are just below the AERO-8’s and the 15” Altec 416 woofers just below the tweeters.

My music is housed on three large Fire Wire external hard drives feeding into the MacMini and then onto either DAC of choice. My musical tastes range from Pop and Rock to Jazz and Classical. I have been collecting mostly high resolution downloads from the usual sources such as, HDTracks, Naim, Linn. Etc….

The AERO-8 fitted OB’s are placed six feet out into the room and about two feet from the side walls (to the edge of the outer baffles). They are toed in so that their beam pattern crosses over about three feet behind my head at seated position, eight feet from the center point of the drivers. Oh, the drivers are also eight feet apart from the drivers’ center point.

The Aero-8 based system does not excite and light up the space between and behind the speakers like the big Lowther based system does. The Lowther system, using the same tweeters, woofers and crossovers brings the recording venue/space to my room by seeming to light up every molecule of air in the front of the listening room. This is a really cool effect. Instruments and voices are seemingly placed in their relative positions that the recording engineer chose in studio.

What the Aero-8 setup does is bring each instrument and voice into my listening room without artificially exciting and lighting up the space between instruments and voices. It is more like I opened my front door and invited the musicians to jam in my room with me their. It is kind of a spooky phenomenon that is hard for me to describe, as I have never encountered it before.
People and instruments, with ALL of their rich tone and dimensionality are simply Alive in the room. Voices are absolutely dead on, including the very hardest part to re-create in a home audio setup, Live Dynamics!

I love powerful voices at live volumes, but almost every speaker system that I have encountered struggles with powerfully Dynamic vocal attacks at live volumes. They almost always tend to thin them out or compress them. The AERO-8’s are the first drivers in my experience to simply cruise right through the toughest vocal attacks in my collection. Nothing changed accept the volume and dynamic hit. Up until now I was under the impression that these issues were in the recordings, not.

The Aero’s high frequencies are as extended as the best full range drivers that I have encountered. However, there is absolutely no bite, shout, or what ever you want to call it. These drivers do not wear on you as many full range drivers with whizzer cones can (yes the AERO’S have whizzer cones). There is no need to toe them out to avoid the center cone pointing directly at your seated position. I prefer to allow the AERO’s to run unfiltered (accept possibly filtering their bass output a bit) with a really good tweeter for augmentation at around 9,000 Hertz.

So, I am impressed with the sonic merits and capabilities of these German made and imported AERO-8, 8” High Voltage field coil full range drivers. BUT I have put off posting my thoughts about these drivers for nearly one year to determine their reliability and if, Mr. Oleg Rullit, their designer and builder, could/would be consistent and available for potential future customers. Well, our communication has been strictly email oriented and not as consistent as I would prefer. But, here we are one year out and Mr. Rullit is still there for me with far more patience than I may have had after nearly a year with no review.

I have often touted how great it is for me to be able to repair my own Lowther drivers at home if the need arises. Especially when you are dealing with drivers from another continent. Lord knows I have needed to realign and or replace diaphragms on more than several occasions.

So, I decided to thoroughly put these German based drivers through their paces. I powered them with voltages all of the way up to 150 and ran them for more than a week straight. Absolutely NO issues. I then decided to find out just HOW DIY capable these drivers are. My experience with the $30.000 plus per pair Feastrex D9eMKII’s got me thinking; what would I do, or be able to do myself if something got into the magnetic gap, or if the voice coils became misaligned. Could I/you fix them myself as with my Lowthers’, or would these expensive drivers need to take a ride all the way back to Japan for even the smallest service need? The answer is, back to Japan every time.

So I did something that I have done hundreds of times with Lowther drivers, I totally dismantled these AERO-8 drivers right down to their motor coils. I was quite surprised at how easy it was to break these beautiful little drivers down with NO risk of potentially damaging them through the process. The four main bolts that hold the diaphragms in place are easily accessed with no concern about the top of the bolts bumping into the bottom of the cones.

The diaphragm easily lifts straight up and off. Then there are just as easily accessible top plate bolts, which also came off with ease. From here I could lift the field coil motor directly out of the case in needed. Everything was SO precisely designed and put together. Not really what I expected from Rullit Atelier. Not because of Oleg, but because he is so damned prolific with his output and seemingly all by himself. But, these drivers were, well, put together with German precision.

Another design benefit that surprised me may require a slight bit of explanation. I have a very unique pair of Lowther PM2MKII magnets. They are not only
Ticonal magnets, but were factory (vary rare) fitted with extra narrow magnet gaps. Lowther knew that even narrower gaps than their already standard narrow gaps sounded even better. However, few if any drivers ever reached the customer without serious voice coil rubbing. This was a very short-lived offering by Lowther and quickly done away with decades ago.

Well, the magnet gaps on the AERO-8’s are smaller than my PM2MKII’s! I ALWAYS have alignment issues when ever switching out diaphragms (from silver to copper for example), or after cleaning the gaps with double sided tape. The AERO-8 diaphragms/voice coils surprisingly dropped right into their skinny gaps with NO rubbing and no time consuming adjustments.

These German drivers went back together like a dream and began to light up my listening room with their unique sonic qualities within minutes. So, I would have “0” concerns about owning a pair of these rugged as hell and wonderful sounding drivers from Germany.

Mr. Oleg Rullit offers these AERO-8, 8” field coil drivers for sale on Ebay for $5,800 per pair.
These are NOT one or two off drivers. I have seen at least thirty of these completed drivers lined up for testing on a workbench at Rullit Atelier.

Oleg, or who ever took the shots, has posted many very clear photos accompanying their AERO-8 posting on Ebay. I have many of my own photos of these drivers dismantled and in position in my listening room. I may post them separately if needed. I tried to incorporate some into this brief review, but it was a mess.

In closing. I seriously hate writing product reviews any longer. I apologize if my posting is less than professional, or worse.

Lance A.

Photos:

http://www.ebay.com/itm/Atelier-Rullit-AERO-8-field-coil-full-range-speakers-No-05-06-/331221780855?pt=Vintage_Electronics_R2&hash=item4d1e5b4977

 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - chopper87@aol.com 18:23:59 06/16/14 (0)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - Retsel 13:00:58 06/16/14 (2)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - rudolf1971 13:54:02 06/16/14 (1)

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 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - chopper87@aol.com 18:23:59 06/16/14 (0)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - Retsel 13:00:58 06/16/14 (2)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - rudolf1971 13:54:02 06/16/14 (1)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - amnesiac 19:49:48 06/20/14 (0)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - youngshooter 20:48:48 06/15/14 (7)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - chopper87@aol.com 17:50:27 06/16/14 (5)
 Vintage rectifiers - youngshooter 19:26:35 06/16/14 (4)
 RE: Vintage rectifiers - chopper87@aol.com 09:00:10 06/17/14 (3)
 Have you used them for amplifier supplies? - rickmcinnis@dogwoodfabrics.com 09:36:03 06/19/14 (2)
 RE: Have you used them for amplifier supplies? - chopper87@aol.com 10:25:28 06/19/14 (1)
 Those 12" woofers are enticing but out of my reach .. - rickmcinnis@dogwoodfabrics.com 11:51:44 06/19/14 (0)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - chopper87@aol.com 09:16:01 06/16/14 (0)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - Diogenes 14:41:08 06/15/14 (0)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - johnsonad 08:19:55 06/14/14 (4)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - mes 09:30:06 06/18/14 (0)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - chopper87@aol.com 08:56:04 06/14/14 (2)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - hottattoo 17:35:15 06/15/14 (1)
 RE: REVIEW: RULLIT ATELIER Aero-8, 8' Field Coil Drivers. - MortenT 13:28:42 03/08/15 (0)