Loudspeakers

Quad is realistic in its claims for the Revela 1 – neither over-rating its sensitivity (86dB/2.83V/1m) or bass extension (40Hz re. –6dB). We'll cover off the detail below, but the Revela 1 is arguably a little tougher to drive than Quad's 6ohm nominal might suggest as the '4.1ohm minimum' is closer to 3.6ohm/221Hz in practice where the sub-100Hz phase angles of +44°/–55° also contribute to a 1.7ohm/130Hz EPDR (equivalent peak dissipation resistance). Above the 2.9kHz crossover, the ribbon tweeter never drops below 6.6ohm (EPDR is >3.5ohm) so the Revela 1 is not a mean HF load for the amplifier. The forward response shows a rise to 20kHz once the ribbon takes over [see Graph 1], offsetting the falling power response of the ribbon due to its reduced vertical dispersion. The latter largely accounts for the response errors of ±3.3dB and ±2.9dB, respectively, and the 1.6dB pair matching, but note the extension of the ribbon out to 60kHz [–6dB re. 10kHz, pink shaded area]. The grille, meanwhile, is best left off for optimal listening [blue trace, Graph 1].

As is also clear from the response plot, the Revela 1 enjoys a far higher 88.2dB/1kHz sensitivity than claimed (or 87.3dB from 500Hz-8kHz) while distortion is good to within ~0.4% from 300Hz-20kHz (re. 90dB/1m). Moreover the relatively 'clean' CSD waterfall [see Graph 2, below] shows no severe breakup modes associated with either driver. The 165mm fibre composite bass/mid unit works over a 67Hz-1.8kHz (–6dB) bandwidth, and with the keenly tuned 40Hz port – also free of spurious output – achieves a very creditable 44Hz bass extension (–6dB re. 200Hz). Overall, the Revela 1 is a very fine all-rounder. PM