Monitor Audio Gold 100 Loudspeakers Lab Report

Lab Report

As is usually the case with compact loudspeakers, the Gold 100 has to make a trade-off between bass extension and sensitivity. The evidence points to MA's design team choosing to sacrifice a little of the latter to improve the former. While the specified sensitivity of 86dB is typical for a reflex-loaded speaker of this size, our measurements show it to be rather optimistic. Our pink noise figure of 84.5dB and 'music' figure of 84.4dB together suggest that 84.5dB is a more realistic figure. But there is payback in the bass extension, which our summed diffraction-corrected nearfield measurements recorded as 44Hz (–6dB re. 200Hz). However our tests also showed a mild 1dB peak at 58Hz before the response drops off rapidly at lower frequencies with the usual reflex fourth-order (24dB per octave) roll-off.

Foam bungs are provided to block the reflex ports should bass performance become boomy as a result of using the Gold 100 close to a room boundary, and with these in place the bass corner frequency rises to 78Hz (–6dB re. 200Hz) but the roll-off rate reduces to second-order. Forward frequency responses for the review pair, measured at 1m on the tweeter axis [see Graph 1, below] demonstrate a commendably flat trend from 700Hz to 12kHz. However, a broad dip at 400Hz and early tweeter peak at 16kHz increase the response errors to ±3.1dB and ±2.6dB respectively – though these are still respectable figures. Over the same 200Hz-20kHz frequency range, the pair matching error is ±1.1dB, the largest disparities being narrow-band between 2.3 and 3kHz. This corresponds with a ridge in the cumulative spectral decay waterfall [Graph 2, below], probably due to a breakup in the bass-mid unit diaphragm. KH

1019monitor.resp

Response has a dip in the upper bass and peak in the high treble but is otherwise flat in trend

1019monitor.wfall

Cabinet is well controlled but the notch at 3kHz in response shows here as a driver resonance

Sensitivity (SPL/1m/2.83Vrms – Mean/IEC/Music) 85.4dB/84.5dB/84.4dB
Impedance modulus min/max (20Hz–20kHz) 2.7ohm @ 3.5kHz, 32.1ohm @ 33Hz
Impedance phase min/max (20Hz–20kHz) –64° @ 2.4kHz, 52° @ 24Hz
Pair matching/Response Error (200Hz–20kHz) ±1.1dB/ ±3.1dB/±2.6dB
LF/HF extension (–6dB ref 200Hz/10kHz) 44Hz / 30.5kHz/30.7kHz
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) 1.2% / 0.6% / 0.2%
Dimensions (HWD) / Weight (each) 360x195x331 / 9.1kg
Price: £1400
COMPANY INFO
Monitor Audio Ltd
Rayleigh, Essex
Supplied by: Monitor Audio Ltd
01268 740580
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