Bookshelf Speaker Reviews

L/R Sensitivity: 89 dB from 500 Hz to 2 kHz

Center Sensitivity: 85.5 dB from 500 Hz to 2 kHz

Surround Sensitivity: 83.5 dB from 500 Hz to 2 kHz

This graph shows the quasi-anechoic (employing close-miking of all woofers) frequency response of the 685 L/R (purple trace), ASW608 subwoofer (blue trace), HTM62 center channel (green trace), and 686 surround (red 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 685’s listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +2.08/–5.86 decibels from 200 hertz to 10 kilohertz. The –3-dB point is at 53 Hz, and the –6-dB point is at 44 Hz. Impedance reaches a minimum of 4.52 ohms at 17.7 kHz and a phase angle of –60.13 degrees at 4.1 kHz.

The HTM62’s listening-window response measures +0.94/–6.38 dB from 200 Hz to 10 kHz. An average of axial and +/–15-degree horizontal responses measures +1.07/–7.01 dB from 200 Hz to 10 kHz. The –3-dB point is at 51 Hz, and the –6-dB point is at 43 Hz. Impedance reaches a minimum of 5.33 ohms at 186 Hz and a phase angle of –48.93 degrees at 84 Hz.

The 686’s listening-window response measures +0.97/–3.00 dB from 200 Hz to 10 kHz. The –3-dB point is at 54 Hz, and the –6-dB point is at 49 Hz. Impedance reaches a minimum of 5.69 ohms at 186 Hz and a phase angle of –58.48 degrees at 96 Hz.

The ASW608’s close-miked response, normalized to the level at 80 Hz, indicates that the lower –3-dB point is at 27 Hz and the –6-dB point is at 22 Hz with the Sub EQ switch set to B and the Extension switch set to A. The upper –3-dB point is at 114 Hz with the Low-Pass Filter switch set to Out.—MJP