Alpine VPA-B222R owner manual Performing Time Correction Manually TCR, Phase Switching, 34-EN

Models: VPA-B222R

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Performing Time Correction Manually (TCR)

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.

1 Check that Defeat mode is off (page 12).

2 Sit in the listening position (the driver’s seat, for example) and measure the distance (in meters) between your head and the various speakers.

3 Calculate the difference in distance between the farthest speaker and the other speakers.

L = (distance of farthest speaker)

– (distance of other speakers)

4 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:

0.5m (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.

5.1ms 0.5m

2.25m

5 Press and hold TA/RTN/SETUP for at least 2 seconds.

The SETUP screen is displayed.

6 Press the joystick up or down to select AP SETUP, then press the joystick right.

The AP SETUP screen is displayed.

7 Press the joystick up or down to select TCR.

8 Press the joystick left or right to select L/R or L+R.

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

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

9 Press the joystick up or down to select TCR SETUP, then press the joystick right.

10 Press the joystick up or down to select the desired speaker.

11 Press the joystick left or right to adjust the calculated time correction value (0.00 to 20.00ms). (1step=0.05ms)

Time correction value changes continuously by pressing and holding the joystick.

12 Press TA/RTN/SETUP to return to the previous screen.

When the speaker is set to the “OFF” mode, the TCR for that speaker cannot be set. Refer to “Setting the Speakers” (page 32).

The adjustment value for FRONT2 (Speakers) which is adjusted in time correction, is also applied to the front speakers in “Setting Bass Focus” (page 36).

The adjustment (AUTO TCR) cannot be automatically set on this unit.

Phase Switching

1 Check that Defeat mode is off (page 12).

2 Press and hold TA/RTN/SETUP for at least 2 seconds.

The SETUP screen is displayed.

3 Press the joystick up or down to select AP SETUP, then press the joystick right.

The AP SETUP screen is displayed.

4 Press the joystick up or down to select PHASE SETUP, then press the joystick right.

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.

5 Press the joystick up or down to select the desired speaker.

6 Press the joystick left or right to switch the phase (0°or 180°).

7 Press TA/RTN/SETUP to return to the previous screen.

34-EN

Page 35
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Alpine VPA-B222R Performing Time Correction Manually TCR, Phase Switching, 34-EN, Check that Defeat mode is off