Home Theater Systems Reviews

Two channels driven into 8-ohm loads: 0.2% distortion at 82.8 watts; 1% distortion at 94.4 watts

Two channels driven into 4-ohm loads: 0.2% distortion at 90.5 watts; protection engages before reaching 1% distortion

This graph shows the quasi-anechoic (employing close-miking of all woofers) frequency response of the KS-908EX L/R (purple trace), SW-38HT subwoofer (blue trace), KS-908EX center channel (green trace), and KS-908EX surround (red trace). All passive loudspeakers were measured at a distance of 1 meter with a 2.83-volt input and scaled for display purposes.

The L/R's listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +3.63/–6.06 dB from 200 Hz to 10 kHz. The –3dB point is at 114 Hz, and the –6dB point is at 98 Hz. Impedance reaches a minimum of 9.16 ohms at 99 Hz and a phase angle of –37.08 degrees at 254 Hz. Sensitivity averages 85 dB from 500 Hz to 2 kHz.

The center's listening-window response measures +1.48/–5.49 dB from 200 Hz to 10 kHz. An average of axial and +/–15-degree horizontal responses measures +1.28/–7.37 dB from 200 Hz to 10 kHz. The –3dB point is at 137 Hz, and the –6dB point is at 124 Hz. Impedance reaches a minimum of 9.53 ohms at 640 Hz and a phase angle of –61.63 degrees at 213 Hz. Sensitivity averages 83 dB from 500 Hz to 2 kHz.

The surround's listening-window response measures +2.18/–4.34 dB from 200 Hz to 10 kHz. The –3dB point is at 141 Hz, and the –6dB point is at 130 Hz. Impedance reaches a minimum of 9.25 ohms at 649 Hz and a phase angle of –59.19 degrees at 224 Hz. Sensitivity averages 82 dB from 500 Hz to 2 kHz.

The SW-38HT sub's close-miked response, normalized to the level at 80 Hz, indicates that the lower –3dB point is at 47 Hz and the –6dB point is at 44 Hz. The upper –3dB point is at 129 Hz.

Crosstalk at 1 kHz driving 2.83 volts into an 8-ohm load was –78.97 dB left to right and –78.80 dB right to left. THD+N from the amplifier was less than 0.151% at 1 kHz when driving 2.83 volts into an 8-ohm load. The signal-to-noise ratio with 2.83 volts driving an 8-ohm load from 10 Hz to 24 kHz with "A" weighting was –83.67 dBrA.—MJP