Alpine DVA-9861Ri Calculating the Time Correction, Inputting the Time Correction, 38-EN

Models: DVA-9861Ri

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Calculating the Time Correction

6 Adjust the cut-off frequency of H.P.F. (HP FREQ) by turning the Rotary encoder, then press MODE.

The adjustable frequency range differs depending on the channels (speakers).

7 Adjust the slope of H.P.F. (HP SLOPE) by turning the Rotary encoder, then press MODE.

8 Adjust L.P.F. by performing steps 6 and 7.

9 Adjust the level (LEVEL) by turning the Rotary encoder, then press MODE.

Press the MODE to return to step 6.

10 To adjust other channels, repeat steps 5 to 9.

11 When the setting is complete, press and hold TA for at least 2 seconds.

The unit returns to the normal mode.

When the speaker is set to the “OFF” mode, the X-OVER for that speaker cannot be set. Refer to “Setting the Speakers” (page 37).

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, if subwoofer is set to STEREO, CENTER adjustment is affected by the subwoofer setting.

When the setting is complete, it is recommended to store the setting contents. For storing, refer to page 44.

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:

0.5m (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.

Inputting the Time Correction38-ENManual backgroundManual backgroundManual backgroundManual backgroundManual background5.1ms Manual backgroundManual backgroundManual background 0.5mManual backgroundManual background

2.25m

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.

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.

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.

Inputting the Time Correction

4 Check that Defeat mode is off (page 25). 5 Press and hold TA for at least 2 seconds.

The audio processor control mode is activated.

6 Select the TCR/PHASE mode by pressing TA repeatedly.

7 Select L+R or L/R by pressing and holding BAND for at least 2 seconds.

L+R: Sets the same adjustment values for the left and right channels.

L/R: Different adjustment values can be set for the left and right channels.

38-EN

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Alpine DVA-9861Ri owner manual Calculating the Time Correction, Inputting the Time Correction, 38-EN