Epos ES14N Loudspeaker Lab Report

Lab Report

The combination of the ES14N's relatively compact enclosure and 178mm mica-loaded polypropylene bass/mid driver does not scream 'high sensivity'. So, while Epos specifies 87dB/2.83V at 1m, our tests suggest 86.2dB/1kHz is closer to the mark, or 85.5dB (500kHz-8kHz) reflecting the slight dip in output before the 28mm alloy/ceramic tweeter takes over above 2.7kHz [see Graph 1]. The tweeter's response roll-offs above 10kHz to –3.5dB/16kHz but rallies somewhat at 20kHz prior to the very well damped resonance at 29kHz [pink shaded area, Graph 1]. This is also visible on the CSD waterfall [Graph 2] which illustrates the generally disciplined behaviour of both drivers within the audioband. Even with this sweetened treble, the mere ±1.9dB response error reveals the impressive uniformity of the ES14N's output, just as the astonishingly tight 0.35dB pair matching indicates excellent production QC. The grille is purely protective and contributes to a ~3dB dip from 3-4kHz [blue trace, Graph 1].

Given the modest sensitivity, 2nd/3rd harmonic distortion is low at <0.3% (100Hz-8kHz re. 90dB SPL/1m) while the speaker's impedance is an undemanding 6ohm nominal – the minimum of 4.3ohm/160Hz shifted from the maximum +50°/–63° swings in phase angle to deliver a very 'driveable' EPDR of 1.8ohm/106Hz. Furthermore, Fink has flattened the ES14N's reactance so its impedance holds to 7-8ohm from 500Hz-8kHz. Enhanced bass extension is another bonus. The bass/mid unit has a 57Hz-460Hz bandwidth (–6dB) – free of cabinet and reflex tube modes – the latter tuned to 37Hz to render a diffraction-corrected extension of 42Hz (–6dB re. 200Hz). This is an expertly-crafted two-way. PM


Response including nearfield bass/mid driver and port [green], freefield corrected to 1m at 2.83V [yellow], ultrasonic [pink]. L, black; R, red; w.grille, blue

Epos ES14N_Waterfall_R_35dB

Aside from some minor modes (500Hz-10kHz), the ES14N is free of substantive resonances

Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC) 86.2dB / 85.5dB / 83.6dB
Impedance modulus: minimum & maximum (20Hz–20kHz) 4.3ohm @ 160Hz, 30ohm @ 64Hz
Impedance phase: minimum & maximum (20Hz–20kHz) –63° @ 77Hz, +50° @ 20Hz
Pair matching/Resp. error (200Hz–20kHz) 0.35dB/ ±1.9dB/±1.9dB
LF/HF extension (–6dB ref 200Hz/10kHz) 42Hz / 26.2kHz/27.0kHz
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) 0.3% / 0.25% / 0.65%
Dimensions (HWD) / Weight (each) 491x250x385mm / 16kg
Prices £3750 (£4400 inc. stands)

Epos Loudspeakers
Essen, Germany
Supplied by: Kog Audio, Coventry, UK
024 7722 0650