Reduction does not always mean simply doing without. Reduction often means focusing on the essentials. Or simply: concentration. The DUO SD, with its single-drive bass unit, is the essence of what makes a speaker – the perfect introduction to the ‘classic sound’ of the DUO range.

PASSIVE VERSION.

The passive version is designed to be used with external hi-fi amplifiers.
With an efficiency of 109dB/W/m and an impedance of 27 ohms, the speaker is extremely easy to operate and ideal for low-power amplifiers. The ideal speaker for the world’s finest high-end amplifiers.

iTRON VERSION.

In the iTRON version, the amplifiers are built into the speaker, eliminating the need for external power amplifiers. To achieve this, we have developed integrated electronics based on fundamentally different electro-physical laws than any other amplifier on the market. We are the first manufacturer in the world to achieve what was previously thought to be an impossible technological feat. For a sound that is simply heavenly.

With our SphericLowCut filter, Airgate technology and PolarizationPlus circuit, we have developed the most innovative technological concepts in our passive crossover.

These are completed with the highest quality components available. Our new NatureCap is an extremely complex capacitor, handmade in Germany. The electrodes are made from precision-rolled aluminium foil, rather than ultra-thin plastic film vaporized with aluminium. The dielectric is a cellulose fibre compound impregnated with organic oils. The NatureCap is approximately 25 times larger than the previous XD series capacitors and is securely mounted to the circuit board using specially manufactured brackets.

For the DUO SD we have developed a completely new drive. Compared to the previous model, we have increased the voice coil from 100mm to 153mm. With this gigantic 6 inch motor structure we achieve absolute top values for the power factor and the power handling, while reducing the power compression.

The motor structure consists of two High Grade magnets magnetised in Europe’s largest 200,000-volt facility. The huge voice coil transfers the power of the permanent magnet with 1.15 Tesla flux density to a voice coil circumference of 480mm. This is an increase of over 50% compared to the previous model!

We use low carbon steel for the pole plates, which are specially designed for the XB12. To ensure high linearity even at maximum diaphragm excursion, the spider has a patented dynamic profile with a progressive surround design. The surround is made of low-loss NBR (Acrylonitrile Butadiene Rubber) for fast and clean transient response.

The diaphragm is made from a composite of long-fibre paper and carbon fibre – extremely strong and torsion resistant for precise pistonic excursion of the diaphragm during transients and decay.

The XB12’s new SingleFrame chassis features robust die-cast aluminium cantilevers, which also enclose the magnet, providing a totally rigid material bond around the moving parts of the motor structure.

The XB12 is our reference in terms of bass. A statement that underlines the uncompromising and unique nature of the G3 Series.

The DUO SD’s active subwoofer is powered by the G3-500 power module. This integrated power amplifier consists of a 500-watt amplifier that provides ample headroom for complex EQ settings.

The subwoofer can be switched on remotely via a 12-volt switching input. Direct connection to integrated amplifiers, power amplifiers or receivers is via speaker-level input terminals. Alternatively, line level inputs are available via XLR connectors. The signal tap is not only high impedance, but also balanced and transformer-coupled. This keeps the circuit ground floating, eliminating hum and making it easy to connect to balanced and bridged amplifier designs.

All electronics are fused via a state-of-the-art E-Fuse circuit. Not only is this much faster and safer than conventional fuses, but it is also ideal in terms of sound.

The bass power amplifier is equipped with an advanced digital sound processor.

The digital crossover eliminates all passive filter elements in the signal path with a precision and bit accuracy that cannot be achieved with analogue technology.

The volume of the subwoofer can be adjusted using the two buttons on the DSP display.

The Avantgarde Control Software allows a wide range of additional settings (e.g. high and low pass filters, equalisers, etc.) to be programmed. The DSP has 2 x LAN sockets, allowing multiple subwoofers to be daisy-chained for simultaneous programming. A USB connection is optionally available.

The user interface has been completely redesigned and is now very easy and intuitive to use. All parameters can be easily adjusted to suit the room acoustics or listening habits.

The BASS-BOOST control can be used to boost the low-frequency response below 45 Hz, allowing the bass response to be adjusted from ‘linear’ to ‘rich’.

The DSP has an 8-band equaliser for individual frequency adjustment. Each of the 8 bands can be raised or reduced by up to 4 dB. This can be used to adjust the bass response to suit a particular sound (linear, techno, pop, rock, classical, etc.) or to reduce certain broadband room resonances.

The LPF-RANGE slider adjusts the upper crossover frequency of the subwoofer and thus the “tonal balance” of the system.

At higher frequency settings, the subwoofer partially overlaps with the midrange horn’s frequency response. This makes vocals/instruments sound ‘warmer’ and ‘fuller’.

When the crossover frequency is set lower, there is a small gap between the subwoofer and midrange frequency response. The tonal balance of the system shifts towards a more ‘dynamic & punchy’ sound.

FILTER 1 & 2 are narrow band ‘notch’ filters with a level cut of -3dB or -6dB. These filters can be used to eliminate/reduce unwanted narrowband room resonance frequencies.