Little British Monitor
The design goal was simple - build the best loudspeaker in a true desktop size of just 12cm x 12cm x 20cm (2.8L). Equally suited to the quality conscious recording engineer, musician or music lover, the LBM II is small enough to fit almost any location, yet capable of filling the space with clean dynamic sound.
Why is LBM special?
Firstly, the LBM II is built by hand, in England, by the designer.
Secondly, the LBM is an audio engineering tour-de-force with sound quality its primary goal. Key highlights are:
Birch plywood cabinets
Linear-phase DSP filters
Class-AB amplifiers
Top quality drivers
Isolated apt-X HD Bluetooth
Micro transmission line bass port
Topping it off, a matching desktop stand has been designed that features a constrained-layer damped surface to isolate and dissipate vibration in the LBM structure.
Enginerding Detail
The details of design and construction set the LBM apart from other desktop loudspeakers. Which areas received special attention?
Micro Transmission Line - The LBM II uses a bass loading technique called a 'transmission line', capable of more extended and tight bass than standard port tubes and usually only found in select large and expensive speakers. This may be the smallest loudspeaker using a transmission line!
Little Feet – Custom designed vibration damping and isolating stands named ‘Little Feet’ are available to match the LBM. The support plate is made using 'Constrained Layer Damping' technique comprising two steel layers laminated using a specific acrylic adhesive. This plate is de-coupled from the stand body with neoprene. The Little Feet design acts as a sink for unwanted vibration that would otherwise pass to your desk or shelf causing colouration of the sound. (Little Feet are an optional accessory).
Class A/B Amplifiers - Practically every current compact speaker uses class-D digital amplifiers. These are small power efficient devices, but not designed with ultimate sound quality in mind. The LBM deserves better. Class-AB analogue amplification has been used in top range equipment for years and now four (one per driver) find their place in the LBM. Class-AB amplifiers require a bigger heatsink and power supply, but reward the user with significantly better sound.
Active DSP Filters - Good drivers and amplifiers mean nothing if they are not working as a cohesive whole - this is the role of a crossover circuit. The LBM combines class-AB amplifiers with modern DSP filtering for a ruler flat response with linear-phase behaviour. This is a huge advantage over ‘powered’ or passive systems, allowing the LBM to play louder and cleaner.
Bluetooth aptX HD - The LBM also incorporates the latest aptX HD bluetooth technology to enable wireless streaming from almost any device. Wireless devices typically introduce electrical noise in audio equipment which can be heard in the background. The LBM isolates the Bluetooth and critical audio circuitry using a regulated virtual ground, achieving a nearly undetectable noise floor without sacrificing convenience.
Frequency and Phase Response - The LBM II is accurate and true; a straight edge by which decisions in audio production can be reliably made. Multi-driver speakers typically distort the timing of the signal (phase) due to energy storage in the system. The LBM II does not distort signal timing. This linear-phase behaviour can only be achieved with the use of DSP filtering.
A useful ‘boundary control’ allows the response to be adjusted to suit your room acoustics. Many speakers have exaggerated bass and treble to sound more impressive than they really are, but the LBM does not need to pretend. The response ranges from 55Hz to 23,000Hz. Recordings are reproduced the way they should be.
LBM II User Guide
LBM II Prototype Reviews (KickStarter Campaign)