from CML Audio is a state-of-the-art, free-space located, stand mounted loudspeaker with a 10 litre cabinet. By virtue of recently introduced balanced mode radiator (BMR) full range drive units, together with careful cabinet design and painstaking voicing, it has an exceptionally high audio performance in relation to its price.

With BMR drive units, the crossover network that divides frequencies between the usual tweeter and bass-midrange drive units is eliminated. The aurally critical
1.5 to 4 kHz frequency band, where the crossover frequency usually resides, is therefore reproduced unadulterated. It is entirely free from phase-related artefacts that can give poor coherence and contribute to listener fatigue and lack of involvement, due to the extra neural processing that is required to assimilate the music being reproduced.

The sound quality obtainable from the Etude 1 is characterised by a pure, liquid nature that  been generally obtainable only from full range electrostatic or magnetically driven panel driver based loudspeakers. The midrange is highly transparent and the treble is naturally extended without the usual spotlighting, (often engineered to give a falsely exciting sound in the demonstration room, or indeed at an Audio Show). Bass response is well controlled with accurate reproduction of bass instrument harmonics that leads to an impression of excellent extension for the size of cabinet. 

The BMR drive units are resiliently decoupled from the cabinet and the cabinet itself is critically braced and damped. The fascia plate further damps the baffle and provides a clean-cut appearance whilst eliminating diffraction effects arising from driver mounting screws and rebates. The cabinet is available in a range of colours, including specific colours selected by the customer, though the latter will incur a small additional cost. An eggshell finish is standard but high-gloss lacquer is available on request at extra cost.

System description

The two BMR drive units in the Etude 1 are series connected but the lower unit has an attenuated high frequency response in order to avoid development of line source behaviour and the associated lobbing effects. In other words the Etude 1 behaves close to a true point source, resulting in excellent resolution of reproduced instrument placement within the sound stage.

Baffle step compensation is achieved via a three element filter that consists of top quality components including a Vishay thick film resistor. The internal wiring is silicone elastomer insulated; good vibration damping is combined with low dielectric absorption.

The bending wave operation of BMR drive units places greater demands on the structural integrity of the drive unit basket/frame and driver mounting, relative to conventional pistonic drive units. In the Etude 1 the driver basket is structurally reinforced with a CNC water jet cut steel element that is bonded in place with industrial adhesive. The drivers are also compliantly mounted on to the cabinet using elastomeric components specifically formulated and designed for dissipation of vibration energy. Metal to metal contact is also kept to an absolute minimum.

Cabinet

The BMR drive units are loaded in a sealed box of about 10 litres volume which is critically braced with hardwood and steel members. The rectangular cabinet walls are divided into asymmetric shapes by hardwood beams that are glued into rebates, this approach attenuates and broadens structural resonant peaks such that they become inconsequential. The front and rear panels are constrained layer laminates. The front panel (baffle) is faced with a 12 mm thick slab of Corian® that is CNC machined to accommodate the drive units and their mounting hardware. The baffles are available in white or a granite black as standard, though paint finishes are available at extra cost. The cabinets are finished in satin epoxy lacquer with black or white being the standard colours; any colour is available at extra cost.