Hi-Fi News Staff

Back in the 1980s, Compact Disc’s tantalising promise of ‘perfect sound forever’ was taken as gospel in many quarters. However, one man was dissatisfied with its performance and set about improving matters with typical fervour. The engineer in question was Stan Curtis of Cambridge Audio and the result of his labours was the CD1 player. Introduced in 1984, it effectively changed the face of CD reproduction – and not just due to its multi-box construction.

Naim Audio’s first product, the NAP 160 power amplifier, was introduced in 1971; the NAP 250 appeared in 1975. It was technically unusual in that it used a strictly regulated power supply, whereas the vast majority of power amplifiers, unlikely today, typically made do with an unregulated one. Arguably, the NAC 12 preamp was even more unusual than the NAP 250. In ultimate form it required a standalone external power supply – the SNAPS – at a time when such an arrangement was virtually unheard of.

KEF’s statuesque Reference 5 embodies an overwhelming amount of research and development – it employs various techniques that are really quite new, but puts together many more that have emerged from earlier design work. The 125mm/25mm driver developed for this new range is the 11th generation of KEF’s Uni-Q designs, while the four 6. 5in bass units are placed as close as possible to this midrange/treble unit to minimise lobeing and interference dips at the crossover point. But rather than having a conventional cone, the bass diaphragm is a shallow aluminium disc, which gives the driver a lower profile and ensures a minimal effect on the frequency response of the midrange and tweeter.

Although the bass and midrange drive units on the twenty. 26 may appear similar to those of the PMC fact 12 [HFN Nov ’13], they are completely new and only found on this loudspeaker so far. The tweeter is the one unit carried over from the existing models and it’s the well proven Solonex 27mm soft-dome unit, developed by SEAS in conjunction with PMC. Its output is rolled off below 3.