Concentric B
Reference bass module, developed in-house
Depth that carries. Control that remains.
Low frequencies reveal their impact not through loudness,
but through stability and control.
The Concentric B is the low-frequency foundation of the LMH N-Series.
Developed for systems that require substance, composure, and physical presence in the bass —
without aggression, without restlessness, without effects.
“Distortion remains just as low at 95 dB as it does at 85 dB — the dynamic limits lie elsewhere.”
— HiFi-Test, 02/22
A foundation is most effective
when it does not have to compete for attention.
The Concentric B was developed for music and film applications where low frequencies are required to provide support, weight, and physical presence — not as an effect, but as a stabilizing element of the overall system.
It does not produce spectacular, inflated bass.
It provides composure, control, and structural stability in the upper and deep bass range.
At the core of the concept is a fully symmetrical construction around the central axis.
The low-frequency driver is positioned exactly at the center of the rotationally symmetric enclosure geometry.
This arrangement creates uniform pressure conditions, constructively suppresses standing waves, and reduces distortion at the mechanical level.
The oval-spherical enclosure geometry with very large wall thicknesses forms a mechanically dominant structure.
Resonances are not damped after the fact, but prevented by design.
The result is low-frequency reproduction that remains precise, extended, and load-stable — even at high sound pressure levels.
The Concentric B follows a clear principle:
Emotion does not arise from agitation, but from control.
The Concentric B is manufactured entirely in the LMH workshop.
The enclosures are produced using precise CNC machining and subsequently finished by hand.
Materials used include European beech plywood as well as solid wood with clearly defined mechanical properties.
This material selection serves exclusively mechanical stability and resonance control.
Resonance-Optimized Enclosure Design
The oval-spherical base geometry, combined with substantial wall thicknesses — up to approx. 80 mm depending on configuration — significantly increases structural rigidity.
Self-resonances are effectively reduced.
The result is low-frequency performance that remains clean, precise, and reproducible — even under high mechanical and acoustic load.
Technical Concept & Design Rationale
This section is intended for readers who wish to understand the acoustic concept of the N°1 in greater detail.
1. System Overview
The Concentric-B is a dedicated low-frequency module designed to extend high-quality loudspeaker systems of the N-Series.
It is not conceived as an effect subwoofer, but as a stabilizing foundation that supplements the upper and deep bass range in a controlled manner, without altering the character of the main loudspeakers.
The goal is low-frequency reproduction that remains supportive, precise, and reproducible — even at higher sound pressure levels and with complex program material.
The Concentric-B enclosure follows a rotationally symmetric geometry without parallel internal surfaces.
The low-frequency driver is positioned exactly on the central axis of the enclosure.
This arrangement creates uniform pressure conditions throughout the entire enclosure volume, prevents the formation of standing waves, and reduces internal resonances by design — without relying on electronic correction.
High-quality neodymium low-frequency drivers are employed in 12″ or 15″ configurations.
The drivers are optimized for controlled excursion, high power handling, and low distortion within their operating range.
The centrally positioned driver arrangement minimizes parasitic cone motion and supports clean, stable force transfer to the enclosed air volume.
The Concentric-B operates as a resonance-optimized bass-reflex system.
Tuning, port geometry, and enclosure volume are deliberately designed for controlled low-frequency reproduction with a high degree of stability.
The objective is not maximum low-frequency extension on paper, but a robust, well-defined bass response that integrates precisely and predictably into existing loudspeaker systems.
The enclosure construction employs substantial wall thicknesses made from European beech plywood.
Depending on the configuration, wall thicknesses of up to approx. 80 mm are used; greater thicknesses are structurally feasible if required.
This mass serves exclusively to reduce self-resonances and to create a mechanically calm operating environment for the low-frequency driver — particularly at high sound pressure levels.
All acoustically relevant components are manufactured or inspected in the LMH workshop.
Large-format components, massive enclosure structures, and tight manufacturing tolerances ensure mechanical stability and reproducible acoustic results.
Measurements are carried out on a project-specific basis and serve final system optimization, including frequency response (on/off-axis), directivity, impedance, and distortion.
Der Concentric-B kann als eigenständiges Tieftonmodul betrieben oder gezielt als Fundament für größere Horn- und Mehrwegsysteme eingesetzt werden.
Durch seine kontrollierte Abstrahlung und stabile Phasenlage lässt er sich flexibel in unterschiedliche Raum- und Systemkonzepte integrieren, ohne den Gesamtcharakter zu dominieren.
System
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Type: bass / low-frequency module
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Enclosure: Concentric-B bass-reflex, rotationally symmetric
Driver
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12″ / 300 mm or 15″ / 380 mm neodymium low-frequency driver
Frequency Range
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up to approx. 25–800 Hz (12″)
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up to approx. 15–600 Hz (15″)
Dimensions (H × W × D)
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12″: approx. 61 × 55 × 63 cm
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15″: approx. 75 × 65 × 73 cm
Weight
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approx. 40 kg (12″)
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approx. 65 kg (15″) per unit
The Concentric-B combines technical integrity with carefully balanced material selection.
Surface treatment and finish are not decorative elements, but contribute directly to the mechanical calm, structural integrity, and long-term stability of the system.
The Concentric-B enclosures are based on a dimensionally stable beech plywood (multiplex) core, offering high dimensional accuracy, uniform density, and well-defined acoustic properties.
Hardwax Oil (standard)
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Clear hardwax oil, open-pored and honest
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Emphasizes natural grain and wood structure
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Acoustically neutral and technically uncritical
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Long-term stable and easy to refresh if required
This finish is the standard configuration of the Concentric-B and underlines the system’s technically focused character.
Clear Lacquer (optional)
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Satin clear lacquer with a calm, controlled layer structure
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Additional protection where specific surface requirements apply
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Preserves the wood appearance without acoustic impact
The clear lacquer serves surface protection and stability only — not visual effect.
Stain & Color Options (project-based)
Project-specific color finishes are also possible for the Concentric-B, provided they suit the application, room context, and acoustic objectives.
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Transparent stains in sensible tones — wood structure remains visible
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Colored oil or lacquer finishes for individual components
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Optional RAL colors for selected surfaces
Colors are not chosen arbitrarily, but coordinated in relation to system design, room, and overall visual balance.
RAL Lacquer (on request)
A fully lacquered execution in nearly all RAL colors is possible where functionally or architecturally appropriate.
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Matte or satin lacquer finish
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Multi-layer, mechanically stable coating system
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No high-gloss or effect-driven surfaces
Here as well, lacquer is a deliberate option, not a default.
Material & Surface Logic of the Concentric-B
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Beech plywood as the structural base — stable, defined, low-resonance
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Surface selection dependent on environment and target performance
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No trend-driven finishes, no decorative effects
The surface treatment of the Concentric-B supports mechanical stability and acoustic integrity — without drawing attention to itself.
