IBX-R4 Loudspeakers

The model line-up now comprises the R25A Anniversary, Avatar R4, IBX-R4, IBX-RW4 and OBX-RW4. Changes are predominantly, but not exclusively, to the crossover circuitry & components, and are a logical development of the work done on the R25A model, which effectively ‘opened a door’ and subsequently embodied a new approach to our crossover design.

All share our favoured MTM (mid, treble, mid) driver configuration, which offers performance advantages over both a simple 2-way design and the more complex but less elegant 3-way option. The MTM topology possesses a more symmetrical polar and more even power response, as well as superior phase characteristics. Factor in higher sensitivity and lower intermodulation distortion and you have an elegant solution even before you design the crossover – a true Occam’s Razor approach. Presenting an easy load and a genuine 94dB sensitivity, each Auditorium model allows class A valve electronics to shine, bringing music to life with verve and vitality.

The elegantly proportioned cabinets and small footprint of the Auditorium Series conceal a meticulous, obsessive approach to the complex problems of loudspeaker design. The Auditorium’s unobstructive natural qualities cut straight to the heart of the musical performance. There is a common DNA from the Avatar R4 up with degrees of refinement, precision of component tolerancing, and overall component quality increasing significantly as you ascend through the range.

In 30 years of loudspeaker development, Living Voice has evolved to the point where around 90% of our crossover components are proprietary. Should we fail to find components that exactly meet our needs, we design in-house and have them engineered to meet our specific objectives – these include film & foil capacitors, non-inductive wire-wound resistors and precision air-core inductors. In this way we can temper the ‘voicing’ to meet our critical musical standards. Most recently, we have developed our own HF unit in conjunction with Scanspeak, a driver which preserves the elegance and filigree of the renowned Revelator but relieves it of a broad energy dip between 10kHz and 15 kHz.

Two 6.5” bass-mid drive units (again a proprietary design made for us by Scanspeak) are used in parallel to produce the equivalent surface area to a single 10” driver – but with half of the excursion and 50% lower intermodulation distortion. Our driver can work cleanly above crossover, facilitating seamless integration with the HF system without the need for steep electrical filter slopes or the use of notch filtering to counteract stop-band break-up modes.

Each Auditorium is ideally suited to exploiting the inherent advantages of class A valve amplification, and has been designed and voiced with the output impedance (and damping factor) of zero/low negative feedback direct-heated Triode designs in mind. In smaller rooms, the 8 watts offered by a single-ended 300B design can be fully realised, however we recommend the use of amplifiers with 15 watts or more to exploit the full dynamic potential available on a broad range of music programme. The dispersion characteristics of the Auditorium Series are such that they create a coherent soundstage even for listeners sitting significantly off-axis. This is emphatically not a ‘hot spot’ design.

Development Process – The Human Factor.
As someone once said, “Not everything that counts can be counted, and not everything that can be counted counts.” It’s a maxim worth repeating in loudspeaker design.

No component is truly benign and there is always a hint of added character, colour or texture which influences the sound. We have literally hundreds of components of different technologies in our R&D library which we can refer to when we are voicing our designs. Finely-honed subjective management of these unmeasurable, unquantifiable characteristics is as important as the strict science of precision crossover filter design. Our crossover designs are the product of three decades of evolution; the goal is the seamless integration of cabinet and drive units to produce an organic ‘out of the box’ listening experience.

We develop all Living Voice loudspeakers using demanding broad spectrum complex musical programmes, with the emphasis being on holistic musical expression, communication, and balance – of creating the illusion of real human beings performing with passion and purpose.

Technical Summary

• High sensitivity, wide dispersion MTM driver topology 750-density hardwood composite enclosure.
• Proprietary hand-wound air-core inductors, mechanically isolated crossover.
• Optimised crossover layout.
• Proprietary non-inductive wire-wound resistors.
• Proprietary Living Voice metallised polypropylene capacitors.
• Treble: Scanspeak 26mm dome tweeter 8ohm. Double ferrite magnet. Fabric dome diaphragm.
• Bass / Mid: Scanspeak 17cm doped paper-coned bass/mid drivers made specifically for Living Voice.
• Woods and finish: Premium furniture grade book-matched natural veneers in Cherry. Walnut. Maple. Rosenut. Black Ash, Flat White.