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| ROYAL DEVICE LAURA STUDIO MK II with MIRANDA HORN TECHNICAL BACKGROUND by Constantine Soo DECEMBER 1, 2003 |
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| Specifications: Type: 2-way back horn loaded full-range speaker system with custom bi-wiring speaker cable. Miranda tweeter horn: modified SEAS ¾ inch soft dome tweeter without frontal phase plug, 24 dB slope filter at 9 KHz with no serial attenuation Woofer: full-range 8 ½ inch custom woofer, crossover-less design with 24 dB high slope with mechanical frontal phase plug for acoustic high-pass filtering and break-up control, no serial attenuation, 9.5 kHz bandwidth with phase reversal triple folded back horn loading Frequency Response: 24 – 20,000 Hz Sensitivity: 98.5/6 ohm, minimum impedance 4.6 ohm @200 Hz (101 dB “A” weighted ambience measurement) Power handling: 1.5 Wpc minimum, 50 Wpc maximum Recommended Amplification: 2 to 8 Wpc single-ended triode monoblocks with 6 ohm transformer tab, and other single-ended tube amplifiers up to 15 Wpc Recommended Amplification: 2 to 8 Wpc single-ended zero feedback triode or better SET amplifiers with 4 or 8 ohms nominal transformer tap. Dimensions: 39.5”H x 10”W x 16” D Weight: 54 lbs. each Finish: handcrafted cabinet in 1 inch Norwegian multi-ply birch wood Price: $10,895 per pair Manufacturer: Aliante s.r.l., Viale dell’Industria 19 – 21052, Busto Arsizio, Varese, Italy Tel. +39 0331 354070 Fax. +39 0331 342445 Direct fax. +39 0331 354903 Website: http://www.royaldevice.com North American Distributor: O. S. Services, Inc. 10153 1/2 Riverside Drive, #159 Toluca Lake, CA 91602 Tel. 818-632-0692 Website: http://www.ossaudio.com |
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BACKGROUND The HE 2003 Show that was co-sponsored by Stereophile in June included a semi-horn speaker system from Italy, the Royal Device Laura Studio Mk II with Miranda Horn. Royal Device is a trademark of the Italian speaker company, Aliante s.r.l. that offers eight special, 2-way high-end horn loudspeakers under the RD name, ranging from the $2,495/pair, bookshelf Legend 6 to the $19,995, floor- standing Lady Diana with the Lady Horn. The subject of this review, the Laura Studio Mk II with the Miranda Horn, is Royal Device’s third most-affordable speaker. Aliante’s proprietor, Roberto Delle Curti, is an electronic engineer involved in analog and digital applications for industries such as audio, automotive, computer, medical, radio and telecommunications since 1972. From a family rich in musical training, Roberto developed a strong affiliation with music and its stereophonic reproduction, using electronics such as the Marantz 1030, 1060, 1120, 1200 & 250, Acoustic Research speakers such as AR 2AX, 3A, 11, 10 Pl, and last not least, the LST which he still owns. After several years experience with studio music production and making amplifiers and mixers of his own, Roberto began experimenting with Klipsch speakers in the late ‘70s, and subsequently came into contact with Paul W. Klipsch, exchanging long letters, article translations, and receiving from Mr. Klipsch all of his Klipsch Audio papers and the Klipsch Dope From Hope, which remains prominently displayed on his desk. To this day, a pair of Klipschorns, Belle Klipsch, and two pairs of Heresy IIs, continue to be integral members of his personal audio room and his lounge. In 1996, Roberto founded his high-end audio company, Aliante s.r.l. shortly after taking over the ownership of a 90-year-old solid wood furniture manufacturer run by a fourth generation family of Italian wood master craftsmen. Since the mid ‘70s, they have been devoted to O.E.M. loudspeaker cabinet production for some renowned Italian speaker companies. The present production plant occupies 13,000 square feet and has 8 employees. Aliante’s Pininfarina line of speakers was their first creation. In addition to seven illustrated articles that Roberto authored on the design concepts of his speakers, his white paper represents the distillation of an unusually complex, lengthy and systematic reasoning on an extreme approach to system synergy. It is Roberto’s belief that just like the creation of a car, each component of an audio system does not stand alone as an independent design goal, but must be designed and evaluated as part of an integrated system. Further, ignoring this principle while building a "best of breed" system will only diminish the potential of the individual components. Ultimately, you’ll compromise overall system performance and musical enjoyment. Towards that ideal, Aliante is the only company other than Britain’s Audio Note and Japan’s 47 Laboratory that I know of that publicizes a significant amount of information on its design philosophies. DESIGN PHILOSOPHY Believing that the loudspeaker was the most problematic member of an audio system for the magnitude of distortions generated in its operation, Roberto insisted on two factors as prerequisites to a good system: 1) the omission of a speaker crossover and 2) amplification feedback. In Roberto’s mind, a 3-way crossover could never restore the acoustic phase coherency within the important frequency range of 60 to 8,000 Hz, because different drivers would load the air with different velocities. Also, the continuously varying transients of music in the form of electrical phase can never be restored once broken up via a crossover’s sine wave-based calculations. Roberto was also critical of the self-reinforcing cycle of modern high-end, low-efficiency speakers and their need for amplifiers with Kilowatts of power and hundreds of watts of output that utilize feedback to maintain operational stability. Thus, high efficiency, 2-way speaker design became his focus. To achieve his design goals with the Royal Device brand of 2-way speakers, Roberto decided to adopt a crossover-less approach utilizing an 8-inch high quality, low weight paper cone woofer on aluminum die-casting to cover the critical range of the first 10kHz. To widen the woofer’s bandwidth while preventing secondary cone break-up, Roberto coupled the woofer to a frontal phase plug for mechanical phase filtering. The woofer back-wave output is horn loaded and triple-folded in the cabinet and a bottom front terminus for bottom-end reproduction. Roberto also set the high-pass frequency for the horn-loaded tweeter at 9kHz, well above the critical midrange band, utilizing the full range woofer to cover the frequencies up to 10Khz, thus avoiding the typical horn "sound" when used in the midrange. The Miranda Horn tweeter is a SEAS soft dome-based horn loaded design utilizing a 24 dB high-pass filter at 9kHz. Roberto states that it has identical phase coherence with the woofer in a 360° delay, thereby negating the need for latter phase inversion. |
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| The Miranda Horn is a standalone unit atop the main unit’s woofer cabinet, and is custom made by the same Aliante master craftsmen. Tweeter interface is via two connectors atop the main cabinet to the tweeter’s soldered cables. Also, the Miranda Horn is a freestanding unit and can be moved front to back to optimize sound dispersion in relation to various listening distances. The tweeter’s phase plug is disposed of to prevent compression and distortion from setting in from the coupling of the soft dome tweeter to the horn. The slender, Norwegian birch wood cabinet appeared ordinary until I inspected the wood closely. The light brown wood surfaces revealed perfectly rounded corner seams and a uniquely sanded skin that I haven’t encountered even in the world of furniture. Subjectively speaking, unlike the wood surface of my Genesis VI, or the meticulously lacquered cabinet of the Audio Note AN- E SEC Silver, the real wood cabinet of the Laura Studio Mk II has a warm and appealing fit and finish. To Roberto’s ears, his Laura and Diana 2-way speakers in their dynamic transients can reproduce a Steinway Grancoda piano better than his $40,000, Bluthner coda piano at the same volume levels via his custom, 2.5 Wpc single- ended tube amplifier. SYSTEM SETUP The Laura Studio Mk II projected an expansive soundstage when given room, and performed optimally in my 12’ x 27’ x 8’ listening room. I placed the speakers 4’ away from the front wall, 2 feet 5 inches from the side walls, and left about 7 feet between the speakers. Nearfield placement hampered the RD’s tonal articulation, while corner placement flattened the speakers’ dimensionality. My wife imposed a new couch upon me that placed my ear height slightly lower right in the middle of my reviewing process. This necessitated a re- adjustment to recapture the integration of the Miranda Horn tweeter and the main driver to my liking. The new couch lowered me to become parallel with the main driver instead, and thus altered the tonal balance. Tilting the Miranda Horn downward slightly improved the driver integration. Moving the Miranda Horn to half an inch from the front edge of the speaker without tilting it completed the speaker’s setup. At this point, better integration was achieved with delicate tweeter horn energy. Slight toe-in was also applied in order to obtain optimal soundstaging sans the horn’s beaming tendency in maximum toe-in. The bass performance from the 8 ½-inch triple-folded back horn loaded woofer was surprisingly potent. Attempts at placing them in corners to increase the speakers’ bottom-end amplitude were unfruitful. This is possibly due to a highly regulated phase behavior from its front-firing horn folded design. For amplification, Royal Device specifically requested that only SET amplification be considered. Thankfully, Randy Bankert of O.S. Services Audio Distribution, Aliante’s North American distributor, provided me with a pair of the $16,000, Audion Golden Dream Level 6 SET monoblocks. |
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| For additional perspectives, I also included Audio Note’s $16,750, Conquest Silver Signature monoblocks, as well as the recently reviewed $15,000 Loth X JI300 Integrated 300B Amplifier, my $3,450, EL34-based Music Reference RM9 Mk II and the twin C-core equipped, $2,450 GW Labs 270 feedback tube amplifier. Preamplification was the $28,000 Audio Note M8. Comprising the digital front-end was the $5,400 47 Laboratory Flatfish CD transport and Audio Note’s $33,000 DAC 5 Special, the Sony SCD-777ES SACD player, with AN’s Sogon digital cable and interconnects completed the system. Royal Device specifies the exclusive use of its proprietary bi-wire speaker cable with all of its models to ensure best performance. Adding banana adapters proved to be consistently detrimental to the RD’s top-end rendition with all amplifiers used in the review. Part II will follow shortly on the auditioning of the Royal Device speakers. |
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