Loudspeakers

The largest model in the Olympica Nova series is specified to have a sensitivity of 90dB, bought in part by a nominal impedance of 4ohm. The first part of that description aligns extremely well with our measurements, which recorded 89.9dB SPL at 1m for a pink noise input of 2.83V. A minimum impedance modulus of 2.8ohm is too low for a 4ohm nominal rating, but in fairness to the Nova V it occurs at a high 14.3kHz. It's also at high frequency – 7.6kHz – that the EPDR (equivalent peak dissipation resistance) dips to its low of 1.5ohm, which makes it less significant in practice because of the, typically, limited musical content in this region.

Elsewhere in the spectrum EPDR is very well controlled, with a narrow dip to 2.0ohm/35Hz and to 2.6ohm/826Hz. So the Nova V isn't as hard to drive as it may first appear. Forward frequency responses measured on the tweeter axis [Graph 1] show a rising output above 4kHz, which strongly suggests the speaker should be auditioned a little off-axis for the most neutral tonal balance. Response errors reflect this up-tilted treble at ±4.8dB and ±4.4dB, respectively, but with careful alignment it should be possible to reduce this to ±3dB or so. Pair matching error over the same 300Hz-20kHz range is disappointing at ±1.7dB but this is largely due to a minor narrowband disparity at 2.1kHz. Without this the figure would have been a respectable ±1.0dB. Diffraction-corrected nearfield measurement showed the bass extension to be 43Hz (–6dB re. 200Hz). The cumulative spectral decay waterfall [Graph 2] is free of resonances in the upper treble but shows three modes associated with the response peaks at 1.2kHz, 2.3kHz and 3.8kHz. KH