Incredible fullrange driver, Rullit 12" field coil in massive horns

Mike Nomad · « **Reply #20 on:** 19 Mar 2011, 11:08 pm »

Quote from: shooter on 19 Mar 2011, 08:45 pm

I have not measure them in these horns, when in open baffle they have plenty of output at 40hz, so I think they will do upper 30's.

Awesome. I don't have a use for anything that can't do at least 40 Hz. I don't miss anything under 30 Hz. Man, I wish I had enough room...

And as others have asked, how many $ was it, etc?

shooter · « **Reply #21 on:** 19 Mar 2011, 11:44 pm »

Well, it is a difficult question for me to answer how much $, the speakers were built by a master furniture maker he is also my best friend and tenant, so there was a lot of bartering on the build. I asked him how much if he is going to build another pair, he told me at least $ 15,000 there is a lot of labor in building the horns, you can see the curves are super smooth all done by hand. As for the drivers, what I bought were prototypes off ebay they are serial number 1 and 2, I don't really know if others like this pair exist or how much if you have to buy from Oleg. Then you have to build a very good power supply, preferably with tube and choke loaded, which all the parts were already at hand and I don't have to buy anything for them, all in all not a cheap project, but they do challenge the very best out there.

JLM · « **Reply #22 on:** 19 Mar 2011, 11:49 pm »

Mike, I'm with you on 30/40 Hz comment.

No way around it, horns get huge to go deep.

These prices make my Bob Brines FTA-2000's look really good ($3500/pair including EnABLing and Behringer DEQ, less efficient, but they reach below 30 Hz in room with AlNiCo magnets).

shooter · « **Reply #23 on:** 20 Mar 2011, 12:01 am »

Hi JLM, your Bob Brine FTA-2000 are really nice, heard them many time at LSAF, my previous speakers were a pair of Lowther DX4 Basszilla diamond edition bi-amped, they are also wonderful, but these horns are in a different league, my system changed from really good hi-fi to almost live.

JLM · « **Reply #24 on:** 20 Mar 2011, 11:38 am »

Impressive comment, I'm sure much of the sense of "live" comes from improved dynamics, which admittedly is probably the biggest fault of the Fostex F200A. The addition of EnABL helps mid/high resolution and DEQ produced flat frequency response helps "make sense" out of the entire extended midrange. I haven't found any other audiophile that has ever heard this combination of enhancements. And BTW, I have a fully compliant Cardas room/setup that really "locks in" imaging.

Wish I could relate better to your story as I don't know you or any of the vendor's products and have never heard large front loaded full range horns. How much bracing is used? IMO that is a major weak point of most horns. OTOH these don't look as deep/restricting as most, so the high pressures/compression and flexing of the horn walls (that all contribute to "horn sound") would probably not be there.

The speakers appear to be acting as open baffle dipoles with limited front horn loading. My experience with open baffles is that they produce a large/diffused soundstage with non-specific imaging, but that the bass loading of the space is quite effective with improved dynamics. Just not my cup of tea. Besides the cost and required room size is beyond my reach.

(No sour grapes here, we each have our slants.) These are striking to look at and read about, and I'm sure are very impressive.

shooter · « **Reply #25 on:** 20 Mar 2011, 02:54 pm »

JLM, Thanks for your reply, I agree with you on EnABLing, it does lower distortion, in 2008 when it was first debuted at the RMAF at the Lowther room in an after hour comparison between EnABLed and non EnABL lowther drivers, there were 4 person in the audition, I was one of the participants, I immediately heard the difference, you can find my comment about that audition buried somewhere in the long DIYaudio thread. About the Rullit drivers someone at DIYaudio commented these driver came with EnABLing in the cone construction already, interesting stuff!
I also own a DEQ to I try to get more warmth out of the low-mid of my home built ER audio ELS3 electrostatic speaker, also a fascinating speakers, amazing sound staging and detail but limited in low bass response, I never got the most out of those speakers after I discovered low power set amplifiers, I changed direction to high efficiency speakers.
The sense of liveness I mention comes from more that just dynamics, it is the combination dynamics and the massive wave front that it can produce that create the sense of scale that is almost impossible to reproduce in direct radiators, the detail came from the solid structure that no cabinet vibration is allowed to blur the sound reproduction, every detail and nuance is just there.
Please check out the link to audio.innerurban posted earlier in the thread, an audio and music site by an audiophile friend whom I met at Dave Slagle and Jeffrey Jackson's room at last year's LSAF, he has just posted his impressions of the horns. BTW Dave's Lowther field coil and Jeffrey's 160hz wood horns are a wonderful combination, it is from that audition that started my journey to commit to build these big wood horns.

RE604 · « **Reply #26 on:** 29 Mar 2011, 07:27 pm »

Quote from: Atelier Rullit on 16 Mar 2011, 11:23 am

By the way, the project mentioned above is, so to speak, high-graded "State of the Art"

Mr. Rullit, do you consider your 15" field coil speakers http://good-times.webshots.com/album/578337836OyipDm to be better than these ones? What is the difference (in emotional aspect) between them?

shooter · « **Reply #27 on:** 31 Mar 2011, 05:09 am »

Can't imagine what size the horns might be, these are already 4' wide and almost 5' tall, I usually sits about 20' away.

Atelier Rullit · « **Reply #28 on:** 7 Apr 2011, 10:22 am »

Quote from: RE604 on 29 Mar 2011, 07:27 pm

Mr. Rullit, do you consider your 15" field coil speakers http://good-times.webshots.com/album/578337836OyipDm to be better than these ones? What is the difference (in emotional aspect) between them?

Hello RE604,

both, the 12" and the 15" field coils, have been developed for a, so to speak, highly "emotional" music reproduction. Yet I cannot define neither as "better", it's a bit like answering the question whether a rallye car is "better" than a formula 1. The 15" has been created specifically for open baffles, while the 12" is designed for front loaded horns.

The decision for either of them depends on the music you are preferring. There are music enthusiasts that you might call omnivores, for they may be as fond of Kraftwerk and Yello as they are for Schumann and Schubert. These should run front loaded horns. Open baffles, in contrast, have to be tailored to the genre of music they are going to play.

At the moment, I'm working on an 8" full range field coil driver Super Aero 8 in a front loaded horn. For the present, it's the terminal stop for me. They are fantastic, playing any music high resolutive and emotionally at the same time.

Kind regards,
Oleg Rullit

RE604 · « **Reply #29 on:** 18 Apr 2011, 08:31 am »

Thank you for the explanation, Mr. Rullit.

I’m also very curious about your new Super Aero project. How did you choose the size of 8”? I’m asking for that, because the bigger wide range drivers have better sense of scale, making the reproduced music more physical and more life-like. I have never used front horns and I don’t have any idea how does an 8” driver loaded with front horn is going to sound. Most of my listening (let’s say >98%) is to classical music, old time jazz and opera. I’m using a pair of 12” field coil wide band drivers, taken from old (1938) radios, which are mounted on big plywood open baffles, but I’m opened for any alternatives if they are going to provide more musical joy to me. Please keep us posted about you new Super Aero speakers when you finish the prototypes

I saw you use special hand made paper in your present Aero speakers: http://field-coil.com/Aero/Aero,%20cones%20&%20coils,%20big.jpg
I suppose you are going to use the same cones for your new Super Aero project , and may be the magnet system will be of your own recipe?

Sam-fi · « **Reply #30 on:** 20 Apr 2011, 08:43 pm »

I love these. I just wanted to add that.

JP78 · « **Reply #31 on:** 17 May 2013, 05:58 am »

Hello,

Some time has passed - any updates on the project?

Best,

Russell Dawkins · « **Reply #32 on:** 17 May 2013, 06:42 am »

I see Atelier Rullit is also making - or has made - compression drivers for horns. I did a search trying to find an active web page (no luck), but did find this large pair of cellulose diaphragm compression drivers currently on sale on eBay for $6900 or $8900; it's not clear.
http://tinyurl.com/bnc6tjr

There seems to be other Rullit action on German eBay - look at some of these drivers!

http://tinyurl.com/cn7xvg6

shooter · « **Reply #33 on:** 20 Aug 2013, 08:14 pm »

I first posted this over 2 years ago, the only change is adding a pair of bullet tweeters from Fostex on top, am still deeply satisfied with its sound, they truly communicate the beauty of music.

Russell Dawkins · « **Reply #34 on:** 20 Aug 2013, 08:34 pm »

Quote from: DavidS on 15 Mar 2011, 01:58 am

stunning!

I love threads like this one and there is a nice thread on these over at diyaudio as well with some input from Mr. Rullit.

Could you provide a link to the particular thread, please?

shooter · « **Reply #35 on:** 20 Aug 2013, 09:01 pm »

I think this is the thread.
http://www.diyaudio.com/forums/full-range/162861-i-want-these-12-field-coil-ebay.html

shooter · « **Reply #36 on:** 30 Sep 2014, 01:25 am »

After more than 5 months of waiting, my patience has been rewarded, just received my pair of field coil Rullit super 8, will need to construct a new power supply for it. Plan to try in open baffle first eventually go into a pair of horns.

ejfud · « **Reply #37 on:** 30 Sep 2014, 01:50 am »

Those look beautiful. Would love to hear a pair of his drivers someday.

shooter · « **Reply #38 on:** 30 Sep 2014, 01:58 am »

Thanks, if you ever comes to Dallas Texas you are welcome for a listen.

beowulf · « **Reply #39 on:** 9 Oct 2014, 01:53 am »

Quote from: shooter on 30 Sep 2014, 01:25 am

After more than 5 months of waiting, my patience has been rewarded, just received my pair of field coil Rullit super 8, will need to construct a new power supply for it. Plan to try in open baffle first eventually go into a pair of horns.

Hi Shooter, what ever became of these drivers and what are your impressions? They sure look the part and BTW the first speakers that you posted are stunning as well!