Alpine CDA-7998 owner manual Bass Focus, 11-EN, → Rl, Example 2. Listening Position All Seats

For setting another channel (speaker), repeat the steps 2 and 3.

Here we calculate the time correction value for the front left speaker in the diagram at the left.

Conditions:

Farthest Speaker – listening position : 2.25 m (88-9/16")

Front left speaker – listening position : 0.5 m (19-11/16")

Calculation: L = 2.25 m – 0.5 m = 1.75 m (68-7/8") Time correction = 1.75 ÷ 343* ⋅ 1000 = 5.1 (ms)

*Speed of sound: 343 m/s (765 mph) at 20˚C

In other words, giving the front left speaker a time correction value of 5.1 ms makes it seem as if the distance to the front left speaker is the same as the distance to the farthest speaker.

The sound is not balanced because the distance between the listening position and the various speakers is different. The difference in distance between the front left speaker and the rear right speaker is 1.75 m (68-7/8").

Time correction eliminates the differences in the time required for the sound to reach the listening position.

The time of the front left speaker is corrected by 5.1 ms so that its sound reaches the listening position at the same time as the sound of other speakers.

Example 2. Listening Position: All Seats

Adjust the time correction level of each speaker to almost the same level.

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

2 Calculate the difference between the distance to the farthest speaker and the other speakers.

L = (distance to farthest speaker) – (distance to other speakers)

3 Divide the distances calculated for the speakers by the speed of sound (343 m/s (765 mph) at 20˚C).

These values are the time correction values for the different speakers.

Bass Focus

The time difference between the front-rear/left-right speakers, can be adjusted at the same time. With an initial delay of 0.1 ms for each of the 0 to 99 steps, audible time correction can be done.

1 Press the T.CORR button to select the Bass Focus mode.

→Bass Focus mode → Time correction mode

Normal mode ←

2 Press the BAND button to select the front-rear / left- right speakers.

FL	FR	FL	FR
→ RL	RR	→ RL	RR
Front (left-right)		Left (front-rear)
speakers		speakers
FL	FR ←	FL	FR ←
RL	RR	RL	RR
Rear (left-right)		Right (front-rear)
speakers		speakers

3 Turn the Rotary encoder to adjust the front-rear / left- right delay.

4

5 After setting, press and hold the T.CORR button for least 3 seconds to return to the normal mode.

NOTES

•Any manual time correction adjustments will also affect corrections made in Bass Focus.

•Bass Focus mode is automatically canceled if no buttons are pressed within 15 seconds.

Continued

11-EN