Epos Model ES-7N loudspeaker Lab Report
The ES-7N, ‘son of ES-14N’, is a tale of two settings – freestanding or on-wall/bookshelf [see boxout]. In freestanding mode the axial response [Graph 1] is flat to within a tight ±1.6dB and ±1.8dB limits (re. 200Hz-20kHz) and sensitivity is 85.4dB /1kHz (or 86.0dB from 500Hz-8kHz), while switching to ‘Wall’ brings sensitivity up by +1.9dB/1kHz and a maximum of +3dB from 2.5kHz-10kHz [orange trace, Graph 1]. In this mode the response error is only fractionally higher at ±1.9dB and ±2.0dB, respectively, and the +12dB tweeter dome resonance [see Graph 2] at 29.7kHz and 40.8kHz unchanged. In all cases the pair matching between these ‘handed’ speakers is an excellent 0.35dB while THD, at <0.1% through mid and treble (re. 90dB SPL/1m), is state-of-the-art for a speaker in this class. Off-axis, the ES-7N retains superb uniformity [grey trace] but the ‘old school’ push-fit grille produces a more significant 5-6dB notch at 5kHz [blue trace] and should not be deployed for ‘serious’ listening.
The ES-7N’s impedance has two dips, at 4.6ohm/232Hz and a lower 2.95ohm/14.8kHz, but with fairly hefty +53/–66° swings in impedance phase below 150Hz it’s the bass EPDR of 1.8ohm/135Hz, not the 1.5ohm/10.3kHz, that will most exercise your amp. Switched to ‘Wall’ the impedance falls to 4.35ohm/285Hz, and sub-5ohm from 160-560Hz, but the bass EPDR is unchanged. The ES-7N’s inherent bass response does not change in either ‘Free’ or ‘Wall’ switch positions – proximity to the wall does this – the 48Hz port tuning augmenting the –6dB/66Hz roll-off of the 130mm PP coned bass/mid unit down to a very respectable 46Hz (–6dB re. 200Hz). PM
Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC) | 85.4dB / 86.0dB / 84.4dB |
Impedance modulus: minimum & maximum (20Hz–20kHz) | 2.95ohm @ 14.8kHz 45.3ohm @ 27Hz |
Impedance phase: minimum & maximum (20Hz–20kHz) | –66° @ 93Hz +53° @ 22Hz |
Pair matching/Resp. error (200Hz–20kHz) | 0.35dB/ ±1.6dB/±1.8dB |
LF/HF extension (–6dB ref 200Hz/10kHz) | 46Hz / 53.0kHz/53.5kHz |
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) | 0.9% / 0.05% / 0.12% |
Dimensions (HWD) / Weight (each) | 290x200x275mm / 7.1kg |