Wall Speaks Page 2


In the lab

Frequency response (at 2 meters) Front left/right 94 Hz to 16.6 kHz ±3.3 dB Center 94 Hz to 14.5 kHz ±3.4 dB Surround 94 Hz to 13.8 kHz ±2.3 dB Subwoofer 39 Hz to 117 Hz ±2.3 dB

Sensitivity (SPL at 1 meter with 2.8 volts of pink-noise input) LCR7 83 dB Impedance (minimum/nominal) LCR7 8.7/14 ohm

Bass limits (lowest frequency and maximum SPL with limit of 10% distortion at 2 meters in a large room) LCR7 80 Hz at 78 dB subwoofer 25 Hz at 92 dB SPL 104 dB average SPL from 25 to 62 Hz 110 dB maximum SPL at 62 Hz Bandwidth uniformity 94%

All of the curves in the frequency-response graph are weighted to reflect how sound arrives at a listeners ears with normal speaker placement. The curve for the LCR7 left/right front channels reflects response averaged over a ±30° window, with double weight at 30° (the most typical listening angle). The center-channel curve reflects response of a horizontally deployed LCR7 averaged over ±45°, with double weight directly on-axis of the primary listener. The surround-channel curve shows the response of the LCR7 averaged over ±60°.


When positioned vertically as a left/right main or surround speaker, the LCR7 displays reasonably moderate irregularities above 800 Hz, with a 2 dB elevation between 800 Hz and 1.5 kHz and stronger peaks at both 3.5 kHz and 12 kHz. A strong combing effect also kicks in at both 45° and 60° off-axis. The LCR7 retains the same basic character when used horizontally, but off-axis lobing causes a 4 dB depression at 8 kHz.

Sub105 Subwoofer

The Sub105 Subwoofer's bass limits were measured with it set to maximum bandwidth and placed in the optimal corner of a 7,500-cubic-foot room. In a smaller room users can expect 2 to 3 Hz deeper extension and up to 3 dB higher sound-pressure level (SPL). Although the sub's crossover is specified as 50 to 200 Hz, the actual operating range only varies between 70 and 117 Hz and there's a 4 dB level interaction over the lower half of its crossover dial. However, the sub's crossover slope is moderate, and its useful operating range extends to 250 Hz (-6 dB). When the LFE input is used there are also fairly radical out-of-band irregularities between 250 and 1000 Hz, although the low-pass filter in your audio receiver or processor should take care of that. The sub proved to have reasonably strong dynamic capability, delivering 104 dB SPL @ 2 meters at 32 Hz and above.