Bookshelf Speaker Reviews

Satellite Sensitivity: 89 dB from 500 Hz to 2 kHz

This graph shows the quasi-anechoic (employing close-miking of all woofers) frequency response of the Ergo 620 satellites (purple trace) and Ergo AS 650.2 SC subwoofer. The passive loudspeaker was measured with its grille at a distance of 1 meter with a 2.83-volt input.

The Ergo 620’s listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +0.79/–3.20 decibels from 200 hertz to 10 kilohertz. An average of axial and +/–15-degree horizontal responses measures +1.17/–2.57 dB from 200 Hz to 10 kHz. The –3-dB point is at 62 Hz, and the –6-dB point is at 52 Hz. Impedance reaches a minimum of 4.98 ohms at 247 Hz and a phase angle of –39.26 degrees at 111 Hz.

The Ergo AS 650.2 SC’s close-miked response, normalized to the level at 80 Hz, indicates that the lower –3-dB point is at 36 Hz and the –6-dB point is at 31 Hz. The upper –3-dB point is at 139 Hz with the Crossover control set to maximum.—MJP