Q Acoustics 3050c loudspeaker Lab Report

This budget floorstander has a flatter forward response [Graph 1] than its costlier 5050 cousin [HFN Jun ’24], trading the latter’s presence band dip and ±4.5dB response error for just ±2.1dB and ±2.15dB, respectively, here. The response trend is slightly U-shaped (BBC-esque) with a small notch at 500-600Hz and a rising treble that offers a 42kHz extension (–6dB re. 10kHz), bettering many high-end speakers equipped with metal domes [HFN May ’25]. A more uniform high treble is achieved by toeing-in the 3050cs by 10-15° [grey trace], at the expense of a 4dB dip at 4-5kHz, while diffraction effects from the magnetically attached grille bring a further disruption to the response above 7kHz [blue trace]. Pair matching is an astonishingly tight 0.5dB (200Hz-20kHz) and tighter still at 0.35dB from 200Hz-10kHz – this is state-of-the-art quality control!

The minor ‘wiggles’ in response are also reflected in numerous low-level resonances in the 142mm C3 bass/mid cones [see CSD waterfall, Graph 2] just as the powerful 32Hz port tuning also exposes minor 860Hz and 1575Hz quaterwave/tube modes [see boxout]. Nevertheless, with the woofers’ matched 55-750Hz (–6dB) bandwidth(s), the port tuning allows the 3050c to develop a respectable 44Hz bass extension (–6dB re. 200Hz). Otherwise, Q Acoustics’ rated 90dB sensitivity for the 3050c is, on test, closer to a lower 88.5dB/1kHz (and 88.4dB across 500Hz-8kHz) but then neither is this speaker quite as tough to drive as the brand’s bigger/higher sensitivity models. The minimum impedance is 3.7ohm/221Hz while a –59o dip in phase angle at 80Hz feeds a 1.75ohm EPDR at 103Hz. PM

ABOVE: Response inc. nearfield summed drivers/port [green], freefield corrected to 1m at 2.83V [yellow], ultrasonic [pink]. L, blk; R, red; grille, blue; ±15°, grey

ABOVE: Cabinet is not as inert as QA’s constrained-layer models. Modes in the C3 drivers appear at 2-5kHz

Hi-Fi News Measured Specifications:

Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC) 88.5dB / 88.4dB / 87.1dB
Impedance modulus: minimum & maximum (20Hz–20kHz) 3.7ohm @ 221Hz
33.2ohm @ 68Hz
Impedance phase: minimum & maximum (20Hz–20kHz) –59°@ 80Hz
+45° @ 521Hz
Pair matching/Resp. error (200Hz–20kHz) 0.5dB/ ±2.1dB/±2.15dB
LF/HF extension (–6dB ref 200Hz/10kHz) 44Hz / 41.5kHz/42.3kHz
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) 0.55% / 0.15% / 0.9%
Dimensions (HWD, inc stabiliser) / Weight 1021x315x316mm / 18kg
COMPANY INFO
Q Acoustics (Armour Home Electronics)
Supplied by: Armour Home Electronics Ltd, Herts, UK
Telephone: 01279 501111
ARTICLE CONTENTS

X