XTZ SUB 8.17 - 8'' Active hybrid subwoofer

SUB 8.17 - Small bass giant with highest precision

The 8.17 is a newly developed subwoofer replacing the well-known 99W8.16 which has a strong fan base among hi-fi enthusiasts. It is astonishing the deep, powerful and yet accurate bass this small subwoofer can create. As the smaller brother of the 10.17 and 12.17, the driver that is used for the 8.17 has been adapted from the Cinema series to provide the highest rigidity and a very low weight. Driven by a newly developed power amplifier which offers 200W RMS and up to 350W peak power, the 8.17 is able to achieve a lower limit frequency of 29 Hz (-3 dB). This subwoofer is the perfect choice for enjoying precise and natural bass.

Driver

The high performance of the driver of the 8.17 is a product of in-house development and has its roots in the driver of the Cinema series which is acclaimed for its performance and precision. This high speed long stroke driver is extremely lightweight yet has maximum rigidity and can therefore follow any signal exactly. Its impulse behaviour is unique and provides maximum accuracy. Combined with the up to 350 W of the Class D power amplifier, both bass thunderstorms and high accuracy are possible at the same time. The high headroom of the amplifier ensures maximum dynamics.

Sound Tuning

Thanks to its numerous sound customization options, the subwoofer 8.17 provides a great deal of flexibility. At the rear terminal, one of the 3 different equalizers can be selected using a rotary knob. While the EQ “REF” provides maximum depth in the bass, “EQ1” cuts the deepest frequencies to adapt the sound to smaller rooms with high room gain. “EQ2” lifts the kick bass to achieve a punchier bass. In addition, the bass reflex tubes can be sealed with the enclosed plugs, whereby the fundamental characteristics of the subwoofer can be perfectly configured. 

Cabinet

To provide the driver with a perfect working environment without disturbing resonances, the cabinet of the 8.17 is made out of 25mm thick MDF. Numerous internal stiffeners provide additional stability and combined with the damping material, a maximum control in the sound. The housing design allows the subwoofer to be operated as a bass reflex box as well as a sealed unit. Due to the perfect size of the housing and its internal volume, the bass is extremely accurate and precise.

Surface

The 8.17 can perfectly be integrated into any home cinema thanks to the three different colors: matte black, gloss black and matte white. The multilayered paint is ornately polished and thus ensures the extremely sophisticated look of the 8.17. Rounded edges provide an even more distinguished look.

Terminal

The rear terminal offers gold plated RCA inputs for minimum connection resistance. Both the crossover frequency, as well as the level of the subwoofer and the phase can be adjusted exactly at the terminal. You also find the rotary knob here for the EQ selection.

Front Cover

The acoustic material which is used for the front grill is opaque and at the same time 100% transparent to sound. The front grill is available in black for the matte black and glossy black version and white for the matte white version. It protects the drivers from potential damage without compromising the sound quality.

Bass Driver

We call this low-mass, long throw driver “high speed” because we use a very lightweight, stiff cone material and a very strong motor (magnet) structure which gives us an incredibly fast driver. It can produce amazing sound pressure levels with great dynamics and yet remain precise and true to the original music. We spent years finding the perfect cone material since the combination of weight and stiffness is one of the most critical factors in driver construction. The material we found that managed to meet all our requirements is made out of a very strong, long fiber pulp blend. The driver also needs to make ultra-long strokes for maximum sound pressure. So to get a maximum of linearity, we had to develop a special NBR (Nitrile Butadiene Rubber) rubber surround. Additional advantages of our custom designed driver include:

• FEA optimized magnetic field design incorporating a tightly focused “T” pole design  
• Advanced level of large signal motor and suspension refinement using KLIPPEL laser-based test system
• Large aluminum shorting ring to minimize inductance and further lower non-linear distortion
• Ultra-high temperature aluminum voice coil with airflow maximizer design
• Special NBR rubber surround with maximum linearity throughout its excursion range
• Spider fabricated from unique blend of poly-cotton

Class-D Amplifier

The SUB 8.17 uses the same type of Class-D amplifier as in our award winning Cinema Subwoofer Series. It has an extraordinary high power output for the driver of 200W with almost twice that in peak wattage output whenever called upon to deliver. In contrast to many other Class-D amplifiers, the design has near ideal clipping characteristics which ensure maximum headroom capability by minimizing the use of limiting circuitry. An unprecedented amount of sound detail and maximum performance are the result of years of design refinement. This amp features an advanced DSP processor. Our DSP gives the amp unmatched control over the driver at all levels with two EQ settings that raise specific frequency ranges. In addition to this high degree of customization, this also allows the subwoofer’s sound characteristics to be changed to your preference for optimized tuning and a more refined behaviour. The internal cabling is realized using 99.99% pure copper wire, which guarantees the highest signal transparency. The structure has low inductance and capacitance.

Sound Tuning

The SUB 8.17 allows you to alter the sound character in many ways. This provides you with options to achieve exactly the kind of sound you want. The bass character can be altered by plugging the reflex ports of the subwoofer with the included foam bungs or by adjusting the EQs on the back. Additional optimization can be done by adjusting, phase, crossover frequency and volume.

EQ REF
Gives an extended frequency response for the deepest bass, however care should be taken to ensure the lower frequencies are not over represented and “muddy”, depending on the room geometrics, placement of the sub and listening position (reverberation).

EQ 1
Is a direct countermeasure to the “muddy” bass problem of over represented low bass/room gain.  By lowering the bass extension, the bass will be more controlled.

EQ 2
Stores more energy a bit higher in the frequency, resulting in a punchier fast bass.

Port Tuning - High frequency
With no plugs in the ports the subwoofer will provide a “quick” and “punchy” bass character. It will produce increased output higher up in the frequency range.

Port Tuning - Mid. frequency
If the left port is blocked and the right port is open, this will provide a bass with an increased output in the mid-region.

Port Tuning - Low. frequency
If the right port is blocked and the left port is open, this will provide a deep bass with an increased output in the lower frequencies.

Port Closed
With both ports blocked the sealed box will provide a dry and controlled bass character.