Loudspeakers

Piega specifies sensitivity in ‘db/W/m’, which implies the speaker has the unlikely property of getting louder the further away you listen, but the 88dB rating still looks optimistic. It also rates the Premium 301 Gen2’s impedance as ‘4ohm’, where the standard 2.83V/1m test would generate 2W rather than 1W (and thereby confer a 3dB advantage), but even here the sensitivity clocks-in at a lower 86.4dB/1kHz, falling further to 84.4dB as a mean value from 500Hz-8kHz. The ‘bump’ in response [see Graph 1] around 1kHz is the result of a powerful quarterwave/rear port tube resonance that punches through to the forward output, and can also be seen on the CSD waterfall [see Graph 2].

This, and the notch in output at the 3.5kHz crossover, is largely responsible for the overall 3.4dB and 2.9dB response errors, respectively, but once the ‘magnetostatic ribbon’ tweeter gets into its stride the output recovers between 5kHz-10kHz before gently rolling away to a modest 25kHz (–6dB re. 10kHz). The grille [blue trace] smooths some of these features at the expense of some ‘vitality’ while a 15° toe-in [grey trace] arguably provides the best balance. Meanwhile, that long, narrow port with its broad 28Hz–120Hz tuning (re. –6dB) otherwise does a fine job of supplementing the 140mm bass/mid unit’s steep roll-off below 110Hz (–6dB/80Hz), bringing the corrected bass extension down to 57Hz (–6dB re. 200Hz). And that nominal 4ohm impedance rating? With a minimum 3.65ohm/230Hz modulus, 4ohm is accurate, but with +50°/–60° swings in phase angle through the bass, the minimum EPDR is a lower 1.54ohm/142Hz, making the Premium 301 Gen2 a fairly tough drive. PM