THE SYSTEM The Duo combines all of Avantgarde Acoustic™s technological and creative potential, resulting in a most sophisticated two way horn system. With its enlarged 670 mm midrange horn, a driver system of exclusive quality and precise integration of all components, this system offers unrivaled performance across the sound spectrum.  The Duo is a 2–way spherical horn system with integrated active subwoofer Sub 225 . Its high sensitivity (104 dB/W/m) and its hybrid concept with self–powered subwoofer makes it easy to drive with any amplifier. Even with low powered tube amps the Duo is able to deliver a powerful, dynamic and three–dimensional sound, because the power–demanding work at low frequencies is managed by the self–amplified Sub 225. THE MIDRANGE HORN DRIVER The outmost care at choosing the drivers is the key to successfully transforming the theoretical advantages of the horn technology into an outstanding High End speaker. As mostly people focus on treble and bass response, Avantgarde Acoustic™ considers the midrange as the “heart” of each speaker system. In the captivating world of horns, size matters: the bigger the dimensions of the horns, the more extended the bandwidth becomes, and the more the listener takes advantage of the incredible performance of the horn technology. That is why our engineers focused all of their expertise to develop a set of unique enlarged spherical horns with an extended frequency range of one full octave – compared to its smaller Uno brother. The result is the spectacular 27 inch spherical midrange horn, seamlessly powered by the high performance M2 driver. The M2 is a 170 mm (7 inch) midrange driver with a 100 mm (4 inch) dome especially developed for the Duo and optimized for a large, linear excursion. A strong ferrite magnet assembly is used to generate a powerful magnetic field which homogeneously controls the movement of the voice coil. The M2 has a very low cut–off frequency with seamingless and crossover–less integration to the subwoofer. The design of the dome ensures a phase–neutral radiation of the sound waves into the midrange horn SH6704 and wide bandwidth of the extended midrange down to 170 Hz.  The kevlar midrange cone of the M2 is coated with trillions of tiny microfibres generating a “Velours Damping Effect”. This incrementally small fur of the VDE technology cone effectively reduces partial resonances of the cone itself. Furthermore the microscopc fibres of the VDE technology help to effectively absorb high frequency distortions. The Avantgarde Acoustic™ proprietary CDC system features a controlled roll–off at 2,000 Hz, and allows us to completely eliminate all passive crossover components in the signal path. This way the M2 gets the pure and non–distorted full–range signal directly from the amplifier! The nominal impedance of the M2 is 8 ohm and the sensitivity is 104 dB (1Watt/1m). THE TWEETER HORN DRIVER The H2 tweeter is a reduced sensitivity version of our reference tweeter H3Ω. The exceptional driver H2 combines the smoothness of an electrostatic driver and the power of a strong 1 inch horn driver. The mere force of the 3 kg (6.5 lb) magnet on the voice coil guarantees 100% detail and precision even at low volume levels, and provides the Duo with compression-free sound reproduction even at extreme sound pressure levels. With the spherical horn SH1801 the H2 offers an ultra wide bandwidth down to 900 Hz. Due to the passive crossover point being at 2,000 Hz we achieve a wonderful smooth sound with incredible dynamic headroom THE SUBWOOFER DRIVER The Duo is supplied with the active subwoofer Sub 225, which is driven by two powerful 25 cm (10 inch) long–excursion drivers. The 10–ND500 long excursion drive unit is characterized by its extremely high efficiency and utmost power handling capabilities. The extended controlled excursion is +/– 7 mm. Exclusive neodym magnets with a special under–pole magnet topology are used to maximize the flux density in the air gap and to eliminate energy leakage of the magnetic field. The powerful neodym magnet with a very strong BL power factor and the very stiff but light membrane will ensure highest resolution and authority even with complex signals at extreme sound pressure levels. THE SUBWOOFER AMPLIFIER The integrated active PA 106 electronics consists of a powerful 250 watt amplifier and an active frequency crossover. A forceful 330VA toroidal transformer and an energy reservoir of 60.000 μF providing ample energy reserves and dynamic headroom.  In order to achieve full control to overcome the inertia of the driver mass, the PA 106 is equipped with Avantgarde´s genuine adaptive motional feedback circuitry. These ultrafast analogue electronics compensate for signal deviations induced by the circuit and drivers in real–time. As a result the Sub 225 achieves an astonishingly flat frequency response down to 18 Hz! Furthermore, even at very low listening levels – when the music signal is too weak to overcome the inertia of the bass driver mass – the adaptive motional feedback circuitry will seamlessly increase its power output for a full and rich bass response. The active crossover allows the adjustment of a number of parameters thus ensuring a very easy and fast installation of the system even in acoustically critical situations. A 3–position subsonic switch, variable settings for the input sensitivity and crossover frequencies make the Sub 225 extremely versatile. The Sub 225 can be remotely switched on/off using the 12V trigger signal. The Sub 225 is driven via high power speaker terminals for direct connection to integrated amps, power amplifiers or receivers or alternatively via XLR terminals. The signal take–off is not only at high impedance, but is also balanced and transformer coupled. This floats the subwoofer ground, avoiding hum loops and eases connection to balanced and bridged amplifier designs. The enclosure of the Sub 225 is constructed from 1.2 inch MDF (28 mm). Designed with a centrally located reinforcing stabilizer, the box construction is very rigid, avoiding resonances. MECHANICAL CONSTRUCTION The midrange horn is mounted into a circular housing cylinder with a solid cast aluminium back cover on its back end. The tweeter is located in a sealed compartment in the upper part of the subwoofer enclosure. The entire loudspeaker system is placed on a solid cast aluminium base frame. The spike assembly of the base frame – featuring solid 55 mm spikes and massive adjusting handles – are easily accessible from the top. Newly designed aluminium spacers with knurled head screws, connecting the frame rails with midrange housing cylinder and subwoofer. A selection of ten standard colors is available for the horns. This includes eight metallic lacquer finishes, the uni–color „Saona Beach Cream“ finish and the moderne „Stealth Nocturne Grey“ finish. The special „Shiny Citrine Orange“ multi–layer coating is available as an option. The front panels can be ordered in any of the above horn colors, plus the elegant „Stealth Nocturne Black“ finish. Four different wooden veneers are available. As standard with matte surface and optional in shiny piano lacquer finish. On this page you will only find a small selection of thumbnails of the color combinations possible. For a better overview you should visit our website www.avantgarde-acoustic.com.  Here you can download a special Color & Finishes.pdf for each product. In this document you can find a nice overview of all front–panel combinations available for each of the horn colors. This will quickly guide you to your favorite horn–panel combinations. COLOR CONFIGURATOR On our website www.avantgarde-acoustic.com you will find as well a comprehensive color selection tool. Just go to the respective product within the HORN–section. Under DESIGN you can select the color of the horn and the color and veneer of the front panel. If you have found your favorite color combination, simply click on the download–button for a high resolution picture (6 mb).