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James Romeyn posted this and other photos on Facebook last night. The color is one briefly offered by Porsche in the late 70s.
Duke is busy finishing the speakers, including the optional grilles, to ship them here very soon, to arrive late next week.
Brian
So much music, so little time!
Follow Ups:
Please accept my apologize for crashing this lovely party, and even worse, a bit late.I developed the radiation pattern employed in Zephrin 46 and Dream Maker LCS, which stands for Late Ceiling Splash. The end of the following thread has links to comments by pro reviewers at 2014 Newport THE Show: http://www.audiocircle.com/index.php?topic=125924.new;topicseen#new
Z46 employs no TL. Each channel of LCS requires two completely separate loudspeaker systems. Z46 houses both channels in one enclosure.
The foundation of LCS is an all-new radiation pattern unlike anything before.
Frosting on the cake is that one stereo pair of an LCS system comprises four separate bass systems. Because each bass system occupies its own unique geographic space, either the L or R (never both) LCS speaker wires with its electrical polarity inverted to damp bass modes. Because LCS output delays at least 10ms vs. on-axis signal from the so-called "Main Speakers," inverting the polarity of one LCS channel is inaudible in the mid/treble range. This feature provides a portion of the natural 3-dimensional bass mode damping feature of a 4-piece Distributed Sub Array. (Side note for attendees at 2013 RMAF who sampled Dream Maker LCS. We did not experiment with this bass mode damping feature till after that show.)
Dr. Floyd Toole and Dr. Earl Geddes associate the following qualities with ideal reverberant field:
1. Full range
2. High output relative to on-axis signal
3. Delayed 10ms-20ms relative to on-axis signal
4. Highly decorrelated relative to on-axis signalLCS provides the above qualities (especially #4) to greater degree than any other radiation pattern and any other loudspeaker. Tekton and Lowther share little if any LCS design philosophy.
The load impedance for each section of Z46 is 16 Ohm, and both impedance curves are very linear above the bass range. Sensitivity is the low 90 dB range. We used two amps at Newport THE Show, one being Atma-Sphere M60, the other a 10-12W transformer coupled tube amp. Neither amp clipped.
The 16 Ohm loads can wire either in series (32 Ohm) or parallel (8 Ohm). It's interesting to note that the higher the load impedance the less is the ratio of speaker cable series resistance relative to the entire load (speaker + cable). The lower is this ratio the less is the audible effect of the cable, with commensurate performance gain.
Ralph's sweet little S30 OTL makes about 40W+ into 32 Ohm load. SS amps make only 1/4 their 8 Ohm power into 32 Ohm, but current capacity increases and distortion spectra improves (less odd order harmonic distortion).
I've got Zephrin 46 setup in my 26 x 16 dedicated dead-quiet well-treated sound room 80 minutes NE of Salt Lake City. Also have Dream Maker LCS but waiting on new smaller LCS 2.0 speakers from Duke.
Note: we intend to offer the new smaller LCS speakers to add to any pre-existing loudspeakers, even dipole and bipole systems. In this case, a power amp with level control is required to drive LCS and match level with the Main Speakers. Price is $2900/pr for the LCS speakers. Sensitivity is low 90 dB range. As per Duke's long standing design philosophy, this new LCS speaker is an easy load with linear impedance curve above the bass range. We estimate bass cutoff "low 30 Hz" with some vertical boundary reinforcement (remember LCS loads directly to the floor, firing upward toward ceiling).
LCS lowers bass cutoff when added to many loudspeakers, dare we say most. More critical than simply lowering bass cutoff and increasing bass power, LCS minimizes bass mode effects, improving bass timing and quality by physically minimizing mode effects in three dimensional space throughout the entire room. Digital EQ manipulates phase, SPL, and frequency in the line level, but it's a zero sum game. Performance degrades at points in the room other than mic test points.
Dual use 2-ch/HT applications: if you ever heard well recorded music played on even the most costly HT system, you were likely unimpressed. I won't explain here why HT loudspeaker architecture is anathema for music. Another Z46 benefit is to allow, for the first time, a dual use 2-ch/HT system with no compromise in either format. Beyond "no compromise," LCS provides rare combination of performance features in 2-ch. For HT applications Front L/R Z46 "phantom center channel" equals any Front LCR array. For music in HT application we believe Front L/R Z46 outperforms any HT Front LCR array regardless of cost or complexity.
James Romeyn, Providence UT
Edits: 09/05/14 09/05/14
wait for it..................you can call them Led Zephrin!
nyuk nyuk nyuk
ET
Edits: 09/04/14
Lousy snapshots taken with my phone; dramatically better photos to come.
Brian
So much music, so little time!
Top to bottom: Kuzma Stabi S/Stogi S, Atma-Sphere UltraViolet preamp and iFi Micro iDSD DAC, AMR CD-777 CD player, and Aurender X100L music server. Atma-Sphere M-60 OTL amps, AudioKinesis Zephrin 46 speakers.
Not yet dialed in but sounding so sweet nonetheless!
Brian
So much music, so little time!
Atma-sphere Ultra Violet preamp???
Ralph Karsten wrote elsewhere:For many years we have been refining a 4- tube circuit (2 tubes if line stage only). We have had many long debates about whether we should market it, as its a departure from our normal stuff; its single-ended (which is the big deal) and is more conventional circuitry. It uses a pair of 6SN7s for the line section and a pair of 12AT7s for the phono section.
However its also a very nice sounding unit, and we've seen it easily take on preamps that cost several times more with no worries. We've had a prototype that we have been playing here at Atma-Sphere for the last 3 years; we know this preamp very well and it really does do the job!
It has a welded chassis, 4 inputs and isn't very big. So far the plan is that they are entirely hand-wired and that has been working quite well. It has vintage styling, but not like our other products. Actually it is the first of a new lineup of amps and preamps.
With the Stepup transformers it works with low output moving coil cartridges and will retail for $2800.00. Without the SUTs, it works with high output cartridges and is $2400.00. Finally, it is available as a line stage for $1900.00. We expect to ship the first units in August.
The unit pictured is on loan from Atma-Sphere and has the Jensen SUTs (white, on the left). It's a little fella that works remarkably well with the M-60s here.
A very similar system should be on demo at RMAF in the AudioKinesis room (room 1100, if I recall correctly).
Brian
So much music, so little time!
Edits: 08/26/14
I assume the unit uses two 12AT7s (in the phono stage) and two 6SN7s per channel, such that maybe the second 6SN7 is serving as a CF in the linestage. Yes? I am glad to see such an "affordable" product from Atma-sphere.
Each 6SN7 is the gain and output of that channel.
Its a very easy preamp to play- it really does not draw attention to itself. There is an Ultraviolet amplifier that will be part of the same lineup.
Taken yesterday shortly before being shipped here.
Brian
So much music, so little time!
Can you say anything about those drivers? Are the rear drivers identical? Two more sets of 3? I suppose I should just call Duke.
The specs are at the link below; a photo of the rear of the speaker is in this article .
Brian
So much music, so little time!
Edits: 08/20/14
Reminds me a bit of the Lowthers (and Tektons to follow) that added a second full range driver firing up.
The theoretical advantage of the configuration we use (developed by Jim Romeyn) is a longer path length to the ceiling, combined with using the cabinet itself to block any side-lobes that would get to your ears early. So we get the sort of time-delay for most of that extra spectrally-correct reverberant energy that you'd get with Sound Labs or Maggies out from the wall at least five feet (long wavelengths will of course wrap around anyway). And imo good things happen when we have that time delay.Or put another way, this technique does what my best bipolars would do (and maybe even better), without demanding you dedicate so much real estate to them. You can plug some ports and shove 'em up against the wall and still get that bipole/dipole type richness and spaciousness.
Duke
Me being a dealer makes you leery?? It gets worse... I'm a manufacturer too.
Edits: 10/02/14
Being a "Porsche guy" (at least as D-wife calls me), that color just fits those cabs!
Can't wait to hear your report on their sound!
"If the audio industry built gear that sounded as good as it did 50 years ago, there would NEVER be a need to re-issued anything!"
It's just that a hole (just visible) at the bottom looks so much like the
driver cutout on the face. But then you can see through that out the back.
Perhaps more photos would help..
The two rectangular cut-outs on the bottom-back are for the inputs, top for the front firing drivers, and bottom for the upfiring drivers.
The other two rectangular cut-outs are for external resistor cups, for fine-tuning the relative loudness of the top end of each section for your specific situation.
The four rear-facing round cut-outs are for the flared ports (2" diameter Precision Ports).
Then we have the two upfiring woofers and four upfiring tweeters (needed that many to get the results I wanted).
So it's a pretty busy box from behind.
Duke
Me being a dealer makes you leery?? It gets worse... I'm a manufacturer too.
Obviously now, this cannot be a TL design.
But this pair will be here by the end of the week, so you can always jump on a plane and find them out. Then you can go upstairs and hear the big system.
Brian
So much music, so little time!
Looks like there are ports on the top surface of the bottom support, at the rear.
I love TLs.
I was thinkin' it looks like driver(s?) go down there .....
But what would be the good of placing drivers there? We'll have to wait for a response.
The internal volume is separated into two chambers, one for the top/frontfiring woofers, and one for the bottom/rear/upfiring woofers.The upfiring woofers get more boundary reinforcement than the frontfiring ones, and of course we take advantage of that.
Both chambers are reflex loaded, with two pluggable ports. So each chamber can be wide open, one port plugged (which lowers the tuning frequency), or both ports plugged (sealed box). That gives, what, nine different combinations per speaker (if my late-night arithmetic is correct) that you can mess with to fine tune the speaker/room interface at low frequencies. I want the low end to be sufficiently adjustable to work up against the wall, or well out in the room, or with Ralph's amps, or (heaven forbid) with someone else's.
Also your bass sources are spread out in all three dimensions, which should help the in-room bass end up a bit smoother even without all the port options.
Duke
Me being a dealer makes you leery?? It gets worse... I'm a manufacturer too.
Edits: 10/02/14
you would not want to close the ports, that would affect the rear impedance of the speaker air interface undesirably. you want an open port which is then presented as the inverse of the port impedance on the back of the speaker.
dee
;-D
True terror is to wake up one morning and discover that your high school class is running the country.
quote by Kurt Vonnegut
If so, I agree. Those ports would be open or else no TL.
I've built two pair of TL woofer systems in my day, one pair of which I dug out of storage to use with my Beveridge 2SW speakers. Mine mimic the classic Bailey design as implemented by Irving M Fried. However, the shape of Duke's cabinet shown in the photo leaves open a question as to what goes where, but odds are that it's a TL, of some kind, IMO.
The splash drivers face upwards and assist with soundstage imaging.
They work quite well too! Duke demonstrated the concept at RMAF last year and again at Newport- they had the speaker set up with a switch so the drivers could be shut off. The soundstage, while still good, is smaller and less focused without them.
I'll bet those do sound nice .... :)
Besides being one of the nicest guys in audio, Duke is also an adventurous and innovative manufacturer. I would love to hear those speakers.
True that.
-
I was, and glad we do not disagree :), closing up the port with a driver would be a strange thing. If they are half wave length...well that would lead some interesting discussions about driving it from both ends.....
dee
;-D
True terror is to wake up one morning and discover that your high school class is running the country.
quote by Kurt Vonnegut
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