Mordaunt-Short Alumni Speaker System HT Labs Measures
Satellite Sensitivity: 84.5 dB from 500 Hz to 2 kHz
Center Sensitivity: 87.5 dB from 500 Hz to 2 kHz
This graph shows the quasi-anechoic (employing close-miking of all woofers) frequency response of the Alumni 2 satellites (purple trace), Alumni 9 subwoofer (blue trace), and Alumni 5 center channel (green trace). All passive loudspeakers were measured with grilles at a distance of 1 meter with a 2.83-volt input and scaled for display purposes.
The Alumni 2’s listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +2.02/–4.38 decibels from 200 hertz to 10 kilohertz. The –3-dB point is at 139 Hz, and the –6-dB point is at 115 Hz. Impedance reaches a minimum of 4.47 ohms at 306 Hz and a phase angle of –41.13 degrees at 179 Hz.
The Alumni 5’s listening-window response measures +1.29/–3.28 dB from 200 Hz to 10 kHz. An average of axial and +/–15-degree horizontal responses measures +1.37/–3.95 dB from 200 Hz to 10 kHz. The –3-dB point is at 137 Hz, and the –6-dB point is at 116 Hz. Impedance reaches a minimum of 4.32 ohms at 310 Hz and a phase angle of –40.87 degrees at 179 Hz.
The Alumni 9’s close-miked response, normalized to the level at 80 Hz, indicates that the lower –3-dB point is at 44 Hz and the –6-dB point is at 38 Hz. The upper –3-dB point is at 148 Hz with the Input switch set to LFE.—MJP