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December 2005 JAS Audio Orsa Loudspeakersby Ken Choi The Orsa is JAS Audio's entry-level speaker and retails for $2299 USD for the pair. It is a fairly compact two-way design that measures 16 1/2"H x 9"W x 13 3/8"D and weighs 24 pounds. The high frequencies are handled by a 4 1/2" aluminum twin-ribbon tweeter sourced from LCY of Hong Kong. This tweeter is bisected along its vertical axis to improve its dispersion characteristics. The midrange/bass driver is a 6 1/4" paper-cone unit sourced from Morel. Overall frequency response is quoted as 45Hz-60kHz. Sensitivity is quoted as 88dB/W/m, with an 8-ohm nominal impedance. The crossover point is at 2400Hz with a second-order filter for the bass and a modified first-order filter for the treble. The crossover network itself is something in which JAS Audio takes great pride, displaying the raw unit as they do at audio shows. High-grade silver wire is used here and for all internal connections. Each driver is housed in a separate enclosure, these being spaced about 1/4" apart by brass discs. The enclosures are manufactured from MDF with rigidity bolstered through internal bracing. Natural wool is used internally for damping. The cabinets are covered with real-wood veneers (rosewood for the review samples) and finished with 14 coats of polyester lacquer. The front edges of the cabinets are beveled to reduce diffraction. The bass-enclosure baffle slopes forward from top to bottom, and Im told that the front of the high-frequency enclosure is slightly tilted downward at an angle of 5 degrees in an attempt at phase and time alignment of the drivers. Perhaps the most unique feature of these speakers are its ports, one for each of the two enclosures, which are opposed to each other at the small gap between the two boxes rather than firing forward or rearward. The manufacturer states that this unusual port orientation improves bass response, minimizes cabinet and room interference, and provides better dispersion for the midrange and bass such that the sound emulates that of panel speakers. Setup I unpacked the stout Orsas and made note of their exceptional glossy finish. The cabinets seemed inert, with no spurious resonance detected. The speakers were installed along the short wall of my dedicated basement listening room that measures 12 1/2' wide by 22' long with an 8' ceiling. After minimal experimentation, the speakers were placed six and a half feet apart with moderate toe-in, about six feet from the front wall, and some eight feet from the listening position. They were Blu-Taked onto 24" stands, which brought the tweeters up to the same height as those of the Wilson Watt/Puppy 7s that I normally listen to in this room. I auditioned the speakers with parts of my main system that might not be typically mated with them but which I felt would amply allow the Orsas to show their stuff and reveal any shortcomings. I was also keenly aware of what (little) this gear would add to the sound of the speakers. The Orsas pair of custom binding posts easily accepted the spades of Purist Audio Designs Venustas speaker cables. Nagra VPA push-pull amplifiers, which output 50 watts of pure class-A, 845-tube power, drove the speakers. The source was EMM Labs CDSD transport and DCC2 converter linked by their optical cables. The DCC2 preamp section drove the Nagras through a pair of Purist Venustas interconnects. The electronics were plugged into a Shunyata Hydra Model-8, which in turn was fed from a dedicated 20-amp line via a Shunyata Anaconda power cord. For comparison purposes, I also used Sonus Faber Guarneri Homage speakers in this same system. After setting up the Orsas, I initially put on Alison Krausss Forget About It [Rounder 11661-0465-2], and what I heard was very disappointing. The speakers sounded muffled and distant, as if they were literally covered by a burlap sack. I considered inadequate break-in as the culprit, but these speakers had much more than the recommended 200 hours on them -- they were the very pair that I'd heard making nice sounds at the Montreal Son & Image show a few months earlier. While Im normally a grilles-on kind of guy, removal of the grilles here resulted in a subtle improvement in clarity, but something was still clearly amiss. The next day, I passed by the speakers and noted thin membranes covering both tweeters. These seemed pretty crudely attached in contrast to the rest of the Orsas fit and finish, but I was loathe to remove them in case they were derived from some NASA-engineered polymer and vital to the speakers integrity. A quick e-mail to the affable Bernard Li of Charisma Audio, the Canadian distributor of JAS Audio products, confirmed that these were simply in place to protect the delicate ribbons while the speakers are in transit. No mention is made of them in the owners manual, but indeed, as Bernard gently pointed out, there was a sheet buried in the packaging instructing the user to remove these tapes before using the speakers. D'oh! One unusual feature of the Orsas is a key-operated Acoustic Performance switch at the back of the speakers, which allows the user to select between Reference and Dynamic settings. No mention of the switch is made in the owners manual, but Im told that active componentry renders the frequency-response curve in the Reference setting flatter such that the speakers are easier to drive. The Dynamic setting allows for more variation of the impedance at midrange and bass frequencies and results in a more forward, dynamic sound. I played with these settings but really could not discern a difference. Perhaps the effects would be more apparent if I were using lower-powered amplifiers. In any event, I did all of my listening with the speakers in the default Reference setting. Sound With grilles and protective tapes off, I cued up "Maybe" from Forget About It and expelled a sigh of relief, knowing that I would not have to spend the next few weeks moving the speakers around and swapping amps and cables in an attempt to improve their very muffled sound. In other words, with the tapes removed, the Orsas were not terribly fussy about placement and produced a full, coherent, slightly forward, and musical sound. Presenting an airy and open view, the speakers disappeared nicely, with Krausss breathy voice locked into the center of the soundstage. An acoustic bass that features prominently on this song was reproduced with satisfying weight and authority. Ive found this recording to be engineered on the hot side of neutral with excessive vocal sibilance reproduced in some setups. This effect was attenuated on the Orsas, leading me to suspect that the speakers may have been designed to accommodate less-than-ideally-produced digital material, perhaps at the expense of accuracy. This is not to say that the high-frequency response was limited; in fact, on other material the highs seemed to extend smoothly and indefinitely. Voices were naturally captured, as with Eric Bibbs "Where the Green Grass Grows," which I listened to from the first Opus 3 SACD sampler (Showcase [Opus 3 CD 21000]). The songs somber opening pedal-organ notes set a melancholic tone. Bibbs voice -- warm and gritty at the same time -- and his sense of yearning were beautifully and realistically portrayed through the Orsas. A soulful gospel choir backs up Bibb on this track, and one can hear and visualize individual singers behind and to each side of him. Further behind the choir is the understated percussion. In my room and with appropriate recordings, depth of soundstage and recording-venue ambience were things these speakers consistently presented very well. A slide guitar, featured in a solo on "Where the Green Grass Grows," is reproduced with uncanny fidelity. Ditto for the didgeridoo featured on "O Ango Tango," another track on Showcase. I became so entranced by the deep, resonating sounds of this primitive wind instrument during a visit to the Australian Outback a few years ago that I hauled one back and still try to play it from time to time. On other recordings the Orsas reproduced acoustic instruments from cello and nylon-stringed guitar to woodwinds and brass with timbral accuracy and a soupçon of warmth, making for a non-fatiguing and truly pleasurable listening experience. While the Orsas emit a full-bodied sound, they dont sound ponderous at all and move the music along in an agile, bouncy way. "Tubby" by Ted Sirotas Rebel Souls is a track from the Naim CD sampler True Stereo [naimcd080]. This tune starts with an infectious reggae-like bass line rhythmically accented by clipped electric-guitar chords with lots of reverb. The bass sounded a bit over-ripe, but it was portrayed with appropriate heft and acceptable articulation. A drum kit at the back of the soundstage then kicks in before saxophones and a cornet reveal the melody. Snare-drum transients were crisp, and cymbals decayed in a delicate and airy fashion. Imaging was reasonably precise, and the soundstage thrown was generous. Staying with the sampler theme, I put on "Lightnin" by the Bill Holman Band from the first JVC XRCD Sampler [JVCXR-0001]. This is a raucous big-band number with plenty of dynamics. The Orsas reproduced the scale of this music convincingly, with big, room-filling sound that belied the compact size of the speakers. I was impressed by how they handled dynamic peaks with little in the way of congestion -- the Orsas can play loud. At higher volumes, massed trumpets displayed a piercing bite that, like the real thing, came close to being uncomfortable, but there was no sense of added stridency imposed by the speakers. Of course, the Orsas could not reproduce the full weight of the big bands bass and percussion section as well as larger transducers might, but the overall presentation was nicely balanced and satisfying. I could live with these speakers without the need for a subwoofer. Shootout When I was asked if I would be interested in reviewing the JAS Audio Orsas, I initially balked because it has been some time since Ive had a serious listen to minimonitors in the $2000 price range. Even in the short term, aural memory is notoriously unreliable for comparing smaller dynamic speakers like these. Really the only way to make valid comparisons is side by side in the same room. Luckily, I maintain a second system in which I use stand-mounted speakers that, thank goodness, I dont change very often. For the past couple of years Ive had Sonus Faber Guarneri Homage speakers ($10,000 per pair) in this system. As I was thoroughly impressed with the performance of the Qinpu A-8000 Mk II integrated amplifier, which, like the Orsas, is distributed by Charisma Audio, I thought that it would be interesting, if not instructive, to put them up against the highly vaunted Sonus Faber speakers. Both are two-way vented-box designs with very similar specifications. The internal volume of the Guarneri Homage is 10 liters, while I estimate that of the Orsa to be about 12 liters. Rather than using the Guarneri Homage's difficult-to-move 36" stands, I simply plopped the Italian beauties down onto the 24" Target stands that the were still warm from the Orsas sitting on them. Thus, the placement of the Sonus Faber speakers was not tweaked to the nth degree, but in this room I previously found them to sound better at this height. The two speaker models sounded surprisingly similar, the differences between them being rather more subtle than obvious. The bass of the Orsas was a tad fuller, but the Guarneri Homages bass was a bit more articulate. Both speakers excelled at reproducing the midrange, with the Sonus Faber speakers sounding somewhat more reticent and refined. Resolution of low-level detail was equally superb, but rendering of dynamics and especially microdynamic shading (the small shifts in volume in recorded music) were a wee bit better brought out with the Guarneri Homages. With respect to the upper registers, Id give a slight edge to the Orsas for their captivating, airy high frequencies. Both transducers presented a warm, richly saturated but transparent sound, with the Orsas producing a more spacious and open soundfield. Aesthetically there was no contest -- I much preferred the sensual curves of the Guarneri Homage to the more conventional sharp geometric angles of the Orsa. If sonic performance were the sole criteria for judgment, this mini-shootout would have the Guarneri Homages winning by a nose for a somewhat more communicative, refined presentation. At less than one-quarter of the price of the Sonus Faber speakers, however, the JAS Audio Orsas came alarmingly close. Conclusion Sure, the music is important. As I write this I am casually listening to the Mercury Living Presence SACD reissue of Rodrigos Concierto de Aranjuez [BMG 475 6184 MSA] playing through the JAS Audio Orsas in the room next door. This music is simply enthralling, but most of you are reading this because youre interested in the sound and performance of the equipment that reproduces the music. Central to the audiophile tenet is how a change of ones gear, however large or small, affects the overall sound of the system. But many of us, regardless of our technological ken, want to take this one step further and ask ourselves why the sound changes the way it does. I have no formal background in any of the audio arts, but that does not stop me from speculating as to why the Orsas exhibit the midrange clarity and throw the expansive soundstage that they do. The unusual port configuration may well be partly responsible for this performance. I suspect that the LCY ribbon tweeter, which extends to over 60kHz, is particularly suited to reproducing high-resolution source material such as SACD, and it should be noted that the EMM Labs digital rig I use converts all PCM-encoded material to DSD. Granted, as one who is firmly ensconced in middle age, my actual hearing of anything above 18kHz would be suspect, but that doesnt mean I could not perceive these ultrasonic frequencies in other ways that make the music sound more real. I was less than impressed in the past by an add-on supertweeter, suggesting that the integration of such ultra-high-frequency devices with the rest of the speaker may be where the real magic is made. Regardless of the how and why, the folks at JAS Audio are clearly onto something good with the Orsa, whose price seems more than reasonable considering the speaker's innovative design and refined performance. A pair of these speakers offers up sound that would appeal to those who favor the warm and musical, as opposed to those of the neutral and accurate camp. I am looking forward to hearing other speakers in the JAS Audio lineup. ...Ken Choi
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