Alpine 9965 Owners Manual - Page 49

9 To adjust other channels, repeat steps 5 to 8. 10 When the setting is complete, press and hold MENU for at least 2 seconds. • When the speaker is set to the "OFF" mode, the X-OVER for that speaker cannot be set. Refer to "Setting the Speakers" (page 46). • Check the playback frequencies of the connected speakers before adjusting. • In order to protect the speakers, there is no OFF setting for the subwoofer low pass filter (the slope remains the same). • The H.P.F. filter cannot be set to OFF (slope OFF) if Tweeter is selected for FRONT1. Or, only the subwoofer is adjustable if STEREO is selected for the subwoofer. • When the setting is complete, it is recommended to store the setting contents. For storing, refer to page 53. Performing Time Correction Manually (TCR)/ Phase Switching Because of the particular conditions inside the vehicle, there can be major differences in the distances between the various speakers and the listening position. It is possible to calculate the optimum correction values and eliminate the time error at the listening position yourself using this function. Calculating the Time Correction 1 Sit in the listening position (the driver's seat, for example) and measure the distance (in meters) between your head and the various speakers. 2 Calculate the difference in distance between the farthest speaker and the other speakers. L = (distance of farthest speaker) - (distance of other speakers) 3 Divide the distances calculated for the different speakers by the speed of sound (343 m/s temperature 20°C). This value is the time correction value for the various speakers. Concrete examples Calculating the time correction value for the front left speaker on the diagram below. Conditions: Distance between farthest speaker and listening position: 2.25 m (88-3/4") Distance between front left speaker and listening position: 0.5 m (20") Calculation: L = 2.25 m (88-3/4") - 0.5 m (20")= 1.75 m (68-3/4") Compensation time = 1.75 ÷ 343 x 1000 = 5.1 (ms) In other words, setting the time correction value for the front left speaker to 5.1 (ms) sets a virtual distance matching the distance to the farthest speaker. 0.5m 2.25m 5.1ms The sound is uneven because the distance between the listening position and the different speakers is different. The difference in the distance between the front left and rear right speakers is 1.75 meters (68-3/4"). Time correction eliminates the difference between the time required for the sound from the different speakers to reach the listening position. Setting the time correction of the front left speaker to 5.1 ms makes it possible to coordinate the distance from the listening position to the speaker. 47-EN