3Com CP-1 owner manual Calibration of the Panorama Program

Connection

and

Calibration

CP-1 Digital Audio Environment Processor

PANORAMA works by canceling the sound going from each speaker to the opposite ear. The effectiveness of the program is highly dependent on the geometry of your front loudspeakers, the room and your listening position. The correct timing of the canceling signal varies with the angle between your main speakers. The SPEAKER ANGLE parameter, displayed in de- grees, adjusts for wide or narrow speaker spacing. For the two canceling signals to arrive at both ears at the same time you must be centered precisely between the speakers. The Listener Position parameter (LISTENER POS) delays the corrections from either channel and allows adjustment for an off- center listening chair or for asymmetrical speaker placement.

Calibration of the Panorama Program

60°

The ideal setup for Panorama is an acoustically dead room, with speakers well away from the walls, and the listener on the center line between the speakers. The effect is diminished by reflections from nearby surfaces. Furthermore, if the listener sees the two speakers from different angles their responses will differ. The addition of acoustic absorption (soft furniture, carpets and drapes) or diffusion (furniture or books that form irregular surfaces and break up reflections) and time spent shifting speakers and chair into more precise alignment (use a tape measure rather than relying on your eyes) will all be rewarded.

Find a mono source, such as an announcer on FM radio or a mono film, and listen for a tightly focused center image of speech or singing. If the image is off-center, adjust the CP-1's BALANCE control. (The narrower the monaural image, the better Panorama will work.) Perform the following setup from a relaxed, comfortable position in your listening chair with your head facing the center point between the speakers.

1.Reduce the volume to about -20 dB. If the display reads: PRESET at the top left, push Program button 2; if not, push BANK, then button 2 to load PRESET PANORAMA WIDE. Push PARAM eight times (until the display reads: CALIBRATE OFF). Push PARAM UP to turn on the left- channel calibration signal.

2.The test signal should appear to come from off to your left side, well beyond the left speaker, with near-total silence in the right ear. Still facing forward, move your head from side to side until the effect is strongest. If you can find the sweet spot from the confines of your chair, go directly to step 4; otherwise perform step 3.

3.Push PARAM once so the display reads: LISTENER POS. Push PARAM UP and DOWN until you hear the strongest effect. Then push PARAM four times, or until the display reads: CALIBRATE LEFT ONLY.

4.Push PARAM UP until the display reads: CALIBRATE RIGHT ONLY. Again, shift your head from side to side to find the sweet spot, this time looking for the point where the silence in the left ear is deepest. Compare the locations of the two sweet spots from steps 2 and 4. If they coincide,

SPEAKER ANGLE is the angle be- tween the main speakers as seen from the listening position -here it is about 60°.

Select Panorama; Push PARAM to display: CALIBRATE; then push Param UP to: ON LEFT ONLY.

NOISE } SILENCE

Move your head from side to side to find the position where the noise is full left, and the right ear hears noth- ing.

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