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Just when I'd gotten the bass problem solved with a proper interconnect, I sent my Slagle TVC off for installation of a ground selector switch. So I used four active tube preamps: a full-function custom-made tube preamp from Japan I have on loan from a friend; my vintage McIntosh C22 tube preamp; my vintage Marantz 7C; and my Hovland HP100. My friend Rich was visiting from Portland again and we went through a number of classical LPs. On the London blue back, Ruggiero Ricci Solo Recita [London CS6193], I was immediately struck by how exceptionally smooth and airy the Gemini tweeters were. This is an incredible tweeter, one that I would rank among the best two or three I have ever heard. This short list would include the plasma gas vintage DuKane Ionovacs and the now-defunct Hill Plasmatronics. (Plasma tweeters are available again in the Acapella speaker line from Germany.)


Playing the Classic Records reissue of Gaite Parisienne [RCA Victor LSC-1817], there was enormous bass but the decay was truncated. Also, there was a disconnect between the wide-open soundstage emanating from the full-range driver and the rather more boxy sound coming from the woofers. After a short period of listening, I found the midrange to be thin due to a lack of lower mids. I contacted Bill Allen about this and he was unsure what was happening but recommended the use of a transformer volume control. Since my Slagle was not available while he was coming out to my side of the world for the May 6th Vacuum Tube Valley Show in New Jersey, he offered to ship me almost his entire system. Though this was a highly unusual offer, I accepted thinking it would let me listen to the speakers synergistically the way he did as well as learn about some interesting products he uses while I was at it.


During the period prior to Bill's equipment arriving, I played a number of CDs through the various preamps. The sound was okay but never really impressive. My Slagle arrived before Bill's equipment so I put it back in the system. Immediately, the lower midrange fleshed out. I found this odd. In other systems, the passive Slagle has always offered wonderful transparency, detail and tonal balance. However, there have been tradeoffs versus really high-end active preamps such as my Hovland or my friend's Ayre. What was happening here struck me as going beyond an improvement based on differences between components that were functioning properly in a given system. I decided to give Bill Allen another phone call to discuss the possibility that there could be some sort of electronic mismatch between active preamps and his woofer plate amps. Keep in mind that both Bill and Robert use TVC preamps at home and for their show demos. Coincidentally, Bill had recently installed an active preamp in his Bastanis Prometheus system and noticed the same effect. Suffice to say that Robert is looking into this phenomenon at the time of this writing. What I can tell the reader is that, based on my experiences, I would strongly recommend the use of a high-quality TVC with the Prometheus in its current form until this is sorted out.


As you might glean, getting to a truly pleasurable listening point with the Bastanis speakers took a great deal of work. But believe me, it was well worth it and I'm personally gratified that I hung in! Let me skip right to my listening notes from when I finally got down to the synergistic component combination as follows:
  • NAD 5000 CD player as transport, digital out through Bill Allen's homemade 75-ohm coaxial digital interconnect
  • Perpetual Technologies P3A DAC with Empirical Audio Turbomod and P3B Monolithic power supply
  • Bill Allen's DIY interconnect to Slagle TVC, Cardas Golden Cross to satellite and woofer amps
  • DIY Hifi Supply Lady Day SE 300B tube amps with Audio Note silver wire, silver foil coupling caps, silver binding posts, my pair of vintage Western Electric 300B tubes and Bastanis-specific tube modification including a single 6SL7 input/driver tube and a 5U4G rectifier tube which differs from the stock Lady Day design
  • Baton speaker cable (copper Hyperlitz with crimped solderless connectors)

Let me start off by saying that the Prometheus Mk. II speakers play all types of music well - very well. The dipole radiation pattern provides exceptional energy and a spacious, wide-open soundstage. Since my mini-monitor Audio Physic Step SLEs are macrodynamically limited, I decided to start off with some large-scale orchestral works for a taste of what I've been missing. I listened to most of the selections below with both the 6B4G-modified Dynaco ST70 and the Lady Day 300B amps. However, the Lady Day amps, with my WE 300B tubes, had so much more resolution and dynamics than the Dyna that I am restricting my comments to listening through the ladies.


The first movement "Proclamation" of Morton Gould's Spirituals in Five Movements [Mercury Living Presence 432-016-2] has a melody played by the string section which alternates with thunderous percussion. The Prometheus speakers acquitted themselves wonderfully, proving to be some of the most dynamic speakers I have heard, certainly among cone speakers. In the fourth movement "Protest" midway through the movement, there is a staccato counterpoint between snare drums and horns, with the strings and bass drums overlaid on this and building in intensity. The Bastanis/Lady Day combination threw a tremendously realistic soundstage, with the horns and snare drums clearly in the rear hall and perfectly rendered in image size and depth.


The fifth movement "Jubile" has a crescendo in the finale worthy of a fireworks display. As the last notes faded away, I found myself involuntarily uttering "Oh my God!" To put it succinctly, I can't remember hearing large-scale orchestral music rendered more convincingly. It was so good that I think it could even convert someone who was blasé about classical music to at least a strong appreciation. I could go on an on with all of the revelations made just with this one CD but let's move on to other genres.


Last summer, my girlfriend and I went to a festival in the nearby shoreline town of Guilford, Connecticut. While she was busy buying trinkets at the jewelry booth, I became entranced by the band playing on the nearby stage. The lead singer/songwriter is Ian Schumacher. I bought his demo CD and was very pleasantly surprised by the recording quality, let alone the cool, fun-bag music. It's got a good-timey Greatful Dead quality with two guitars, keyboard and drum kit. Looking at Ian's website, I see that he was on long-term visit here in Connecticut but has since returned to his home base in Atlanta, Georgia. Do check him out. Ian, please come back to Connecticut!


Track one is "Way Back Home". This song flat out rocks. The cymbal crashes on this cut really illustrated the capabilities of the sensational -- optional upgrade -- Gemini tweeter. What is astonishing about this horn-loaded dipole compression tweeter is its combination of raw power and refinement with absolutely no trace of harshness. To my ears, this tweeter really puts just about everything I've heard out there -- diamond, beryllium, whatever -- to utter shame. Again, you better have the amp with the refinement and moxie to show it off. With the WE 300Bs, the cymbal crashes on this cut were a revelation. I now feel that almost every tweeter I've heard previously slightly smeared cymbal crashes and robbed them of their real life and nuance.


The opening of track four "The Candle" exploded into the room with powerful acoustic guitar riffs. Later in the cut, there is some trippy Jerry Garcia-style electric guitar noodling that just makes you want to reach for your tie-dyed T-shirt. The ability of the Lady Day-powered Bastanis to push out the tremendous dynamics in this song while at the same time allowing total access and complete comprehensibility of the minute inner detail was almost overwhelming at times. I thought my head was going to explode.


I used to think mainly of bass when I reflected on PRaT (pace, rhythm, and timing) before. The Gemini tweeter has redefined this concept for me. Listening to the R&B bar band CD I picked up at CES two years ago -- Ronnie Rathers' Nut'n But A Groove (no label or website but an e-mail contact) -- I found myself realizing how much the cymbal work was driving the rhythm, just as much in fact as any other element of the percussion.


A friend of mine at my gym has been complaining about the lack of dynamics in his system (B&W, Rotel, Lexicon, Velodyne, MIT) and asking my advice. I've been trying to get him out of his mainstream audio brand mentality. Here was my chance. I invited him to come over and listen to the Bastanis and then take an excursion to the local high-end salon another day. We bounced around between his system, mine and the dealer's. We listened to the new Wilson Duette powered by a McIntosh solid-state integrated amp, then the Duettes and Sophia 2s over a complete Ayre rig.


As we probably all do when coming home from listening to somebody else's system, I played the same CDs to take proper measure once back in my digs. In the interest of kindness to the nice folks at this audio salon, all I will say is that I think Dave Wilson better get back to work. The Sophias sounded colored by comparison and the level of information retrieved was about half that of the Bastanis. What with the Lady Day amps dialed in with my Baton speaker cables and Cardas Golden Cross interconnects, my friend came over to listen once again. When I played a CD he had heard many times before, he got very quiet and displayed an ashen look on his face. It was one of those rare moments when you see someone's entire audio paradigm come crashing down all around them.

My record and CD collection is weak in Blues but one CD I cherish is the Rhino compilation Albert King, The Tomato Years, R2 71623. To paraphrase one of Albert's own song titles, this is what the Blues is all about. As the eighteen-page biographical liner notes state, "many a time his playing would induce in the audience an almost religious-like trance."


The last four live cuts, three recorded at Montreux, "I'm Gonna Call You As Soon As the Sun Goes Down", "That's What The Blues Is All About", "I'll Play The Blues For You" and "Blues At Sunrise", capture this religious fervor and are some of the most realistic live recordings I own - not because the recordings are cleaned up and doctored but just the opposite. They capture the down-and-dirty simpatico between Albert and his adoring audience, with all of the random stage (amp buzzing) and crowd noises you'd expect to hear. The Bastanis reproduced the live ambience of this recording better than anything I have ever heard - truly thrilling.


The encoded imaging on these live Albert King recordings is very natural, with a wide open soundstage and plenty of depth. The Bastanis-style reproduction of this imaging is not like the Audio Physic Step SLE speakers in my downstairs system. The Steps will carve out the boundaries of each player in a solid, three-dimensional way, with an almost concrete density to the image. The Bastanis fullranger, as I have found with other dipole speakers, has less weight or density to the image. This is a minor point but some listeners may notice it. I would not classify this as a criticism. It's simply a difference I hear between box and dipole speakers.


My earlier criticism of a somewhat boxy coloration associated with the bass quality was largely ameliorated when I switched to the Slagle TVC. Still, the bass cabinet cannot really compete with the airiness and transparency of the open baffle drivers. Listening to the standup bass on the cut "Upper Manhattan Medical Group" of Art Farmer's Something To Live For: The Music of Billy Strayhorn [Contemporary CCD-14029-2], there was more of a boxy coloration than I hear from my Audio Physic Luna subwoofer downstairs. Again, this is minor and rarely detracted from my enjoyment of the music as an integrated whole. In my audio fantasies, I wonder what an open-baffle dipole subwoofer such as a Celestion 6000 or Enigma would sound like with the Bastanis speakers. Of course, such designs are restricted in dynamic headroom. It might introduce another set of issues matching a sub with the wideband drivers.


As I promised near the beginning of this review, I replaced the Gemini tweeters with the standard tweeters in my final day and a half of listening. I was relieved to find that the standard tweeters are actually very good and still better than most of today's offerings. However, the Gemini tweeter, like the widebander, is truly world class. You have to expect to lose something when you downscale from there. What you give up is the intoxicating air and transparency plus high-frequency dynamics. All that translates into a more exciting sound. I would have to say that even though the price tag on the Gemini tweeter upgrade seems steep at $800/pr, it's worth it.


Now that I've covered just about all of the design innovations, tweaks and options for the Bastanis Prometheus Mk. II, I'd like to step back for a moment and take a look at the big picture. I am clearly gushing over these speakers, something my Editor and fellow moonies probably thought they'd never see me do. While I do think that the Bastanis speakers are truly exceptional, I need to add an important caveat. More so than any speaker I've ever had in my possession, the Bastanis demand the highest-quality, purest, hot-rodded front end you can muster. As Bill's latest change to his website says, "less is more". In particular the combination of a TVC and excellent SET amp takes the Promethians to an entirely different level.


These speakers are like a high-powered microscope on anything you insert upstream. Bill Allen kept stressing how they were extremely revealing of the true qualities of upstream components and cables. I would present a slightly different perspective. The speakers are so revealing and the changes wrought by inserting different upstream cables or components so large that they can be easily thrown off balance. When it's right though, it's fantastic. When it's not synergistic, the sound can be rather mundane.


Whichever way you want to spin the chameleon aspect of the Bastanis speakers' performance, Bill Allen himself has
become increasingly aware of it. In fact, Bill recently expressed that he is considering marketing the speakers as a complete system, with the electronics and cables he already sells on his website. That seems like a good idea to me. It avoids someone hearing the speakers and being disappointed.


I decided to hold off on submitting this review until after the Vacuum Tube Valley Audiophile and Music Exposition in New Jersey this past weekend. This would give me a chance to hear the speakers in another setting and with the setup experience of Bill Allen. Bill's technique is to put the speakers a few feet from the front wall and then incrementally move them into the room until image height becomes realistic. He then tried toeing the speakers in slightly but ended up with them firing straight ahead as apparently Robert Bastanis prefers.

There were several important differences that made the sound at VTV different from what I achieved in my room. Bill used: 1) TJ mesh plate 300B output tubes vs. my vintage WE 300B; 2) DIY upgraded power cords on the Lady Day amps; 3) Audio Alchemy Pro CD transport using the I²S output connector to the Empirical Audio turbo-modded Perpetual Technology 3A DAC. Both the TJ mesh plate 300B tubes and the I²S link served to smooth the presentation and give it a richer, more romantic quality. In my opinion (and Bill agreed), the vintage WE 300B tubes provide a more incisive sound with greater detail and transparency. The last change he made was to install his DIY power cords. This afforded a surprisingly large improvement to the dynamics and soundstage air. For my money, the Bastanis Prometheus Mk. II speakers were making some of the best sound at the show.


For all of you fullrange driver fanatics -- especially Lowther fans -- why not give yourself a break and audition the Bastanis speakers? I think you'd find just about everything you love about the Lowther sound (e.g. midrange purity, tremendous detail and speed), but with real bass, complete composure on all types of music, better dynamics and none of that pesky upper midrange peakiness.


I will be purchasing both the Bastanis Prometheus Mk. II speakers and hopefully, the Lady Day amps. (Finally, I will be able to dedicate my squirreled-away NOS WE 300B tubes to a worthy cause.) As my Editor will attest after living vicariously through my personal quest to get satisfactory high-efficiency speakers for future vintage tube amp reviews, the fact that I am buying the Promethians speaks volumes. I'm not an easy man to please it seems.


In the end, I think the best analogy for the Bastanis Prometheus Mk. II speakers is that they are like a thoroughbred race horse - perhaps Seabiscuit. They will sneeze at inferior electronics and can be quite temperamental and off-putting to a lesser jockey but with the best tack and rider, they will lead you into the winner's circle with The Triple Crown.
German mother website
US satellite website