MBL 101 X-Treme MKII Radialstrahler System


MBL 101 X-Treme MKII Radialstrahler System

The crown jewel of MBL’s legendary product line, the 101 X-Treme system never fails to astonish – in looks or sound. Our flagship transducer is comprised of two six-foot tall towers that each house a pair of MBL’s iconic Radialstrahler omni systems, flanked by another pair of six-foot subwoofer towers to create an extreme four tower system. Beyond their aural purity and objet d’art presence, each Radialstrahler tower features a pair of MBL’s proprietary high, mid, and low-frequency spherical drivers that capture the inimitable MBL audio signature. Purposefully configured in a stunning vertical mirror array, the 101 X-Tremes distribute sound to every corner of your listening space. Meticulously hand-crafted from carbon fibre, copper, aluminum and magnesium, the revolutionary mirror array allows the 101 X-Treme to project music farther without increasing the volume.

Within each omnidirectional tower are unique driver membranes that deliver micro-precise, lightning-fast movements to produce accurate, distortion-free sound in all frequency ranges. The massive pair of enclosed subwoofer towers, each loaded with six 12-inch drivers for a total of twelve 12” aluminum cone woofers, plumb the bottommost reaches of your favorite bass lines using a push-push arrangement to perfectly counter any unwanted cabinet resonances. With heavy sandwich-core construction and an eye-watering system weight exceeding one ton, structural transmission of sound doesn’t stand a chance.

Challenging room acoustics?  Smoothly managed with passive jumpers on the back panels to fine-tune the bass, midrange and treble. Each subwoofer is designed to be located diagonally behind the crowd-stopping Radialstrahler towers, with the option to stack up to three sections in a classic pillar, or align them horizontally as three individual modules. Extensive control options, including time delay and Q factor of each channel’s sub-bass, overcome virtually all architectural impediments to magnificent, room-filling sound.

From stygian bass notes to the brightest octave treble clef, the MBL 101 X-Treme MKII System represents the pinnacle of pure musical enjoyment – all from a loudspeaker so exquisitely crafted that only twelve systems are produced every year.


“This is the most realistic stereo system I’ve ever heard.”

Jonathan Valin, The Absolute Sound



Mids and Highs

Tweeters and midrange drivers are the heart of every loudspeaker. Without the critical frequencies they produce, it’s almost impossible to capture the emotional nuances of voices and instruments. This frequency range covers most of the vocal spectrum while allowing listeners to pinpoint the location of players or instruments within the original recording space.

Refined to perfection over the past 40 years, MBL’s Radialstrahler technology enables full 360-degree distribution of sound waves to fill entire rooms with concert-hall majesty, creating a truly immersive spatial experience. And this holds true for all listeners, not just one or two individuals located in the sought-after sweet spot or sound apex of two conventional loudspeakers.

MBL’s technology also bests the geometric design challenges of most living rooms, where multi-angled reflective surfaces and protuberances cause reverberation, making it difficult to reproduce lifelike music. Our one-of-a-kind Radialstrahler technology, used in all tweeters and midrange drivers throughout our speaker lineup, smoothly overcomes edges, angles and reflective planes for the ultimate listening enjoyment.

Tailor your sound

MBL loudspeakers are meticulously crafted to achieve the audio grail of neutrality. But what if the design of your listening room is less than perfect (as most are)? Or you want to tailor the sound to your individual components? Jumper sets on the back of the 101-X-Treme radial towers allow pinpoint adjustments to suit your tastes, with separate tunings available for the low, mid, and high range.

High frequency listening

Three different wire-types between the crossover and tweeter allow you to fine-tune your music. In the Natural setting, high-quality, solid-core copper braid provides perfect neutral balance. The Fast setting uses the unique conductivity of silver-plated copper wire to open up the sound of damped rooms or warm sounding components. The Smooth position runs the music signal through a solid core copper wire – a perfect solution to counter the sharp, nervous highs often found in reverberant rooms (think stone floors, large windows), or by other bright-sounding elements in the system.

No-compromise, liquid midrange

The Natural setting delivers on its name – transmitting music signals through an air coil to the midrange driver, and delivering a very neutral sound. In Rich mode, the signal runs through an iron powder coil, effectively promoting the delicate timbre of the lower midrange to the benefit of demanding listening rooms and components. Searing vocals and the gentle tickle of ivories never sounded so expressive.

Bass Charge

The Attack position adds a capacitor to the signal path, altering the phase response to allow signals to arrive at the bass melon a tick earlier than to the other drivers. The low-midrange sounds drier with more structure – extremely well suited for bass-heavy listening rooms when compared to the Smooth setting.

Subwoofer Presence

Each six-foot subwoofer column consists of active enclosures powered by a built-in MBL amplifier that cleverly allows for sound adjustments. The Delay control allows the phase response of the playback system to be delicately adjusted from minus to plus eight milliseconds – particularly helpful when the subwoofer tower is not positioned directly next to the main Radialstrahler tower. The Volume dial adjusts the overall output levels of the subwoofers, providing listener options. For example, if one of the sub-frequency columns is close to a wall or in the vicinity of a corner, the level can be reduced by up to 6 dB. If located in a more open space, the level can be moved by +6dB. The Q-Factor control affects the tonal quality of the sub bass from 0.5 (stronger attenuation) to 1.0 (lower attenuation). The result can take the listener from a slender, contoured bass response to a more voluminous, chocolate-rich bass. And the latest MKII generation of the subwoofer includes a 2-band parametric equaliser that can emphasise or diminish individual frequency ranges, allowing it to adapt to different listening rooms.

The 101 X-Treme MKII at a glance

  • The pinnacle of MBL’s speaker rangeslineup – supremacy without compromise
  • Impressive natural and surround sound reproduction thanks to sophisticated Radialstrahler technology
  • 4-way, four tower loudspeaker system with active subwoofers and ambient tweeters
  • Can be integrated into medium to large rooms (40-120 m²; 440-1300 ft²)
  • High, mid and low-frequency drivers in a mirror array (D’Appolito arrangement)
  • Active subwoofers in separate towers containing a total of twelve 12” (30 cm) aluminum sandwich drivers with over 500 liters (18 ft³) of enclosure volume
  • Parametric equalizer and extensive options to adapt to listening room/media room acoustics or musical taste
  • A total of 26 drivers make up the complete speaker system
  • 942 kg (2,077 lbs) total system weight

Technical Specifications

System 4-way system with double tweeters, midrange and woofers (D’Appolito arrangement), ambient tweeter and active subwoofer
Acoustic center 100 cm / 39”
Subwoofer Active subwoofer, each channel 6 x 12” aluminum cone drivers in three cabinets, push-push arrangement, cabinet volume 3 x 86 liters
Woofer Radial TT100, copper-alu-magnesium
Midrange Radial MT50, woven carbon fiber
Tweeter Radial HT37, unidirectional carbon fiber
Lowest frequency 24 Hz
Crossover frequencies 85 Hz, 600 Hz, 3 500 Hz
Nominal impedanz 2 Ohm each channel 4 Ohm each upper/lower unit
Nominal power handling / Peak each channel: 2 x 900 Watt / 2 x 1 800 Watt
Dimensions (WxHxD) Radial system: 496 x 1 854 x 687 mm / 195” x 730” x 270” Subwoofer: 410 x 1 860 x 670 mm / 161” x 732” x 264”
Weight Radial system: each channel 265 kg / 584 lbs Subwoofer: each channel 227 kg / 500 lbs Total system: 984 kg / 2 170 lbs
MBL xtreme
MBL xtreme MBL xtreme



MBL 101 X-Treme MKII Radialstrahler System Demo