QUAD L2 Series manual Technology, Technical Improvements

L2 Series

Technology

Designing loudspeakers is still very much an art form, yet modern materials and components allow us to push the performance envelope further than ever before.

Neodymium magnets are used in the L2 tweeters. These are a form of ‘rare-earth’ super-magnet. Because they are so strong and small, when properly employed, they create a very concentrated magnetic field – ideal for the small excursions required for a good high-frequency response.

Whilst most moving-coil tweeters use copper voice-coils, we have developed for the L2 series a new wound aluminium alloy voice coil

–capable of higher power handling that the copper equivalent, with better thermal stability and a wider bandwidth. This is largely responsible for the improvements to detail and resolution over the original L-series. A good bass driver chassis design is essential for smooth mid-range. A poor

chassis creates reflections from the cone movement that are passed back through the cone and cause a temporal smearing effect, akin to ‘ghosting’ of a television signal.

At Quad, we are fortunate as we have the capability of designing and manufacturing any chassis structure. With our own tool shop, die-casting machines, and drive unit assembly plant, we can control the complete process from design to manufacture.

The L2 series uses a new low-profile version of the 4-arc driver chassis used in the original L-series. While the same curved, self-bracing design is used, all the legs are now profiled and narrowed to minimise cone reflections.

The audiophile grade crossover is carefully orientated to minimise magnetic induction and, on bookshelf models, we have added our unique twin port arrangement (designed to reduce distortion by up to 50%).

Technical Improvements

Metallised Polypropylene low-loss capacitors are used in an audiophile grade crossover. All components are mounted on glass-fibre PCBs with non- interlacing tracks. Perfect layer, air- cored inductors are used, mounted cross-axially to preventmagnetic intermodulation.

Internal bracing is applied to even the bookshelf models now, designed specifically to randomise the internal reflections and cause rapid dissipation of internal standing waves for a clean, fast bass response.