Monitor Radius Speaker System HT Labs Measures
This graph shows the quasi-anechoic (employing close-miking of all woofers) frequency response of the Radius 90 satellite (purple trace), Radius 360 subwoofer (blue trace), and Radius 180 center channel (green trace). All passive loudspeakers were measured at a distance of 1 meter with a 2.83-volt input and scaled for display purposes.
The Radius 90's listening-window response (a five-point average of axial and +/–15-degree horizontal and vertical responses) measures +2.55/–3.14 decibels from 200 hertz to 10 kilohertz. The –3dB point is at 124 Hz, and the –6dB point is at 96 Hz. Impedance reaches a minimum of 5.02 ohms at 66 Hz and a phase angle of –38.91 degrees at 179 Hz. Sensitivity averages 84.5 dB from 500 Hz to 2 kHz.
The Radius 180's listening-window response measures +1.24/–3.67 dB from 200 Hz to 10 kHz. An average of axial and +/–15-degree horizontal responses measures +1.32/–3.40 dB from 200 Hz to 10 kHz. The –3dB point is at 110 Hz, and the –6dB point is at 87 Hz. Impedance reaches a minimum of 5.07 ohms at 326 Hz and a phase angle of –37.62 degrees at 154 Hz. Sensitivity averages 84.5 dB from 500 Hz to 2 kHz.
The Radius 360's close-miked response in the audio mode, normalized to the level at 80 Hz, indicates that the lower –3dB point is at 54 Hz and the –6dB point is at 43 Hz. The upper –3dB point is at 219 Hz with the frequency control set to maximum.—MJP