Alpine 68-13530Z42-A About Time Correction, Example 1. Listening Position Front Left Seat, 37-EN

Page 39

About Time Correction

The distance between the listener and the speakers in a car vary widely due to the complex speaker placement. This difference in the distances from the speakers to the listener creates a shift in the sounds image and frequency characteristics. This is caused by the time delay between the sound reaching the listener’s right versus the left ear.

To correct this, this unit is able to delay the audio signal to the speakers closest to the listener. This effectively creates a perception of increased distance for those speakers. The listener can be placed at an equal distance between the left and right speakers for optimum staging.

The adjustment will be made for each speaker in 3.4cm steps.

Example 1. Listening Position: Front Left Seat

Adjust the time correction level of the front left speaker to a high value and the rear right to zero or a low value.

5.1ms 0.5m

2.25m

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").

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

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*1 × 1000 = 5.1 (ms)

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

In other words, giving the front left speaker a time correction value of

5.1ms makes it seem as if its distance from the listener is the same as the distance to the farthest speaker.

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 correction value to the farthest speaker and the other speakers.

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

These values are the time correction values for the different speakers. Setting these values to make each sound reach the listening position at the same time as the sound of other speakers.

Time Correction Value List

Delay

Time

Distance

Distance

Delay

Time

Distance

Distance

Difference

Difference

Number

(cm)

(inch)

Number

(cm)

(inch)

 

(ms)

 

 

 

(ms)

 

 

0

0.0

0.0

0.0

51

5.1

173.4

68.3

1

0.1

3.4

1.3

52

5.2

176.8

69.7

2

0.2

6.8

2.7

53

5.3

180.2

71.0

3

0.3

10.2

4.0

54

5.4

183.6

72.4

4

0.4

13.6

5.4

55

5.5

187.0

73.7

5

0.5

17.0

6.7

56

5.6

190.4

75.0

6

0.6

20.4

8.0

57

5.7

193.8

76.4

7

0.7

23.8

9.4

58

5.8

197.2

77.7

8

0.8

27.2

10.7

59

5.9

200.6

79.1

9

0.9

30.6

12.1

60

6.0

204.0

80.4

10

1.0

34.0

13.4

61

6.1

207.4

81.7

11

1.1

37.4

14.7

62

6.2

210.8

83.1

12

1.2

40.8

16.1

63

6.3

214.2

84.4

13

1.3

44.2

17.4

64

6.4

217.6

85.8

14

1.4

47.6

18.8

65

6.5

221.0

87.1

15

1.5

51.0

20.1

66

6.6

224.4

88.4

16

1.6

54.4

21.4

67

6.7

227.8

89.8

17

1.7

57.8

22.8

68

6.8

231.2

91.1

18

1.8

61.2

24.1

69

6.9

234.6

92.5

19

1.9

64.6

25.5

70

7.0

238.0

93.8

20

2.0

68.0

26.8

71

7.1

241.4

95.1

21

2.1

71.4

28.1

72

7.2

244.8

96.5

22

2.2

74.8

29.5

73

7.3

248.2

97.8

23

2.3

78.2

30.8

74

7.4

251.6

99.2

24

2.4

81.6

32.2

75

7.5

255.0

100.5

25

2.5

85.0

33.5

76

7.6

258.4

101.8

26

2.6

88.4

34.8

77

7.7

261.8

103.2

27

2.7

91.8

36.2

78

7.8

265.2

104.5

28

2.8

95.2

37.5

79

7.9

268.6

105.9

29

2.9

98.6

38.9

80

8.0

272.0

107.2

30

3.0

102.0

40.2

81

8.1

275.4

108.5

31

3.1

105.4

41.5

82

8.2

278.8

109.9

32

3.2

108.8

42.9

83

8.3

282.2

111.2

33

3.3

112.2

44.2

84

8.4

285.6

112.6

34

3.4

115.6

45.6

85

8.5

289.0

113.9

35

3.5

119.0

46.9

86

8.6

292.4

115.2

36

3.6

122.4

48.2

87

8.7

295.8

116.6

37

3.7

125.8

49.6

88

8.8

299.2

117.9

38

3.8

129.2

50.9

89

8.9

302.6

119.3

39

3.9

132.6

52.3

90

9.0

306.0

120.6

40

4.0

136.0

53.6

91

9.1

309.4

121.9

41

4.1

139.4

54.9

92

9.2

312.8

123.3

42

4.2

142.8

56.3

93

9.3

316.2

124.6

43

4.3

146.2

57.6

94

9.4

319.6

126.0

44

4.4

149.6

59.0

95

9.5

323.0

127.3

45

4.5

153.0

60.3

96

9.6

326.4

128.6

46

4.6

156.4

61.6

97

9.7

329.8

130.0

47

4.7

159.8

63.0

98

9.8

333.2

131.3

48

4.8

163.2

64.3

99

9.9

336.6

132.7

49

4.9

166.6

65.7

 

 

 

 

50

5.0

170.0

67.0

 

 

 

 

 

 

 

 

 

 

37-EN

Image 39
Contents IDA-X305S Page Contents Operating Instructions SAT Radio Receiver Optional Installation and Connections Operating Instructions On Handling USB Memory Double Action Encoder Operation Getting Started Turning Power On and OffAdjusting Volume Setting the Time and CalendarPress View How to View the DisplayRadio Displaying the Calendar/TimeListening to Radio Presetting Stations ManuallyPresetting Stations Automatically Tuning to Preset StationsAbout iPod/iPhone usable with this unit Changing the Display HD Radio mode onlyIPod/iPhone 10-ENTo pause playback, press PlaybackSearching for a desired Song/Title 11-ENSearch Position Memory Up/Down Function12-EN Changing the Display Random Play ShuffleRandom Play Shuffle All Repeat Play14-EN Pandora Radio iPhoneListening to Pandora Thumbs Feedback15-EN Searching for a Desired StationBookmarking a Desired Song or Artist QuickMixUSB memory/ Portable audio player/Changer 16-ENChanger CD screen display example if no CD text exists 17-EN Selecting a Disc Changer OptionalMulti-Changer Selection Optional Select the desired Folder Folder up/ down MP3/WMA/AACPress /ENTER during play X. Random PlaySearching for CD Track Number CD changer only 18-ENUSB memory mode About MP3/WMA/AAC19-EN 20-EN TerminologySetting the Bass Bandwidth Sound SettingSetting the Bass Control Setting the Bass Center FrequencyTurning Subwoofer ON/OFF Setting the Treble ControlAdjusting the High Pass Filter Press to return to normal mode23-EN Bluetooth SettingPress and hold for 2 seconds to return to normal mode Setting the Bluetooth Connection Bluetooth24-EN General Setting25-EN Display Setting26-EN IPod/iPhone SettingHD Radio Setting Only when HD Radio Tuner is connected Audio Setting27-EN SAT Radio Receiver OptionalReceiving Stored Channels Storing Channel PresetsReceiving Channels with the SAT Radio Receiver Optional Checking the SAT Radio ID NumberStoring while receiving a game broadcast Canceling the stored Alert Memory Sirius onlyGame Alert Setup Press to cancel the Function modeInstant Replay Function Sirius only Search FunctionSelect the desired Category Category up/down Receiving Weather or Traffic Information from SAT Radio31-EN Setting the Auxiliary Data Field Display32-EN Changing MultEQ modeAdjusting Sound Setting in Manual Mode Imprint Operation OptionalSetting the Subwoofer Phase Setting the MX LevelEqualizer Presets Factory’s EQ Setting the Subwoofer System34-EN Setting the Filter typeSetting the Time Correction Unit Sound Field Adjustment35-EN 36-EN Storing and Recalling the Adjusted Contents37-EN About Time CorrectionExample 1. Listening Position Front Left Seat Example 2. Listening Position All Seats38-EN SUBW. Mode3WAY Mode About the CrossoverCase of Difficulty InformationIndication for Portable audio player Mode Indication for USB memory40-EN Indication for SAT Receiver Mode Indication for CD Changer41-EN 42-EN Specifications43-EN Installation and Connections44-EN Installation45-EN 46-EN Connections47-EN This Warranty does not cover the following Limited Warranty
Related manuals
Manual 49 pages 35.94 Kb