Thứ Năm, 9 tháng 9, 2010

suy hao trôû khaùng loa & daây loa

Suy hao đường dây loa


For the best speaker damping and least amount of power loss you will want to use the heaviest gauge that is practical. The length of the speaker wire should be considered when considering wire gauge. The shorter the run, the smaller gauge you can use with minimum power and damping factor loss. The longer the run, the heavier gauge you will need to minimize power and damping factor loss. You will also want to consider the size of power amplifier you are using. The larger the amplifier, the heavier gauge you will want to use. Generally speaking, runs of 25 Ft or less work well with 14 gauge. Over 25 one should use 12 gauge if possible. These numbers are not set in stone, but generally work well. For Constant Voltage systems such as a 70.7V or 140V systems, the voltage is high and the current is low. Because there is not much current you can use smaller wire without much power loss. Quite often 18-gauge wire works well with these systems.

TAÀM QUAN TROÏNG CUÛA DAÂY LOA VÔÙI HEÄ THOÁNG AÂM THANH

R=(K.L)/d2


R: Trôû khaùng daây loa [Ohm]
K: Trôû khaùng chaát lieäu daây daãn [Ohm/circular mil food]
L: Chieâu daøi ñöôøng daây [feet]
d: Thieát dieän daây daãn [mm]

Ghi chuù:
-                           Neáu ñoä daøi daây loa (khoaûng caùch amply ñeán loa) laø l thì chieàu daøi ñöôøng daây maø ñieän tích chaïy töø + Amply ñeán loa vaø ñeán – Amply seõ laø L=2l
o       Ví duï khoaûng caùch töø amply ñeán loa laø 30m thì chieáu daøi ñöôøng daây seõ laø 60m
-                           1 foot (ft) = 0.3048 (m)

SUY HAO ÑÖÔØNG DAÂY LOA

Ñoä daøi ñöôøng daây vaø thieát dieän daây, chaát lieäu duøng saûn xuaát daây daãn laø nhöõng yeáu toá cuoái cuøng aûnh höôûng ñeán aâm thanh.
Chaát lieäu – hôïp kim duøng saûn xuaát daây daãn caøng tinh khieát, ít oxy hoùa, daãn ñieän toát thì caøng toát
Baûng ñaùnh giaù trôû khaùng  moät soá kim loaïi:

Material
Symbol
Resistance (Ohm/Cir Mil ft)
Selenium
Se
7.30
Sliver
Ag
9.71
Copper
Cu
10.37
Gold
Au
14.55
Chromium
Cr
15.87
Tungsten
W
33.22
Molybdenum
Mo
34.27
Potassium
K
42.70
High-Brass
Cu-Zn
50.00
Phosphor-bronze
Sn-P.Cu
57.38
Nicel, Pure
Ni
60.00
Iron
Fe
60.14
Platium
Pt
63.80
Palladium
Pd
65.90
Tim
Sn
69.50
Tantalum
Ta
79.90
Manganese-Nickel
Ni-Mn
85.00
Steel
C-Fe
103.00
Lead
Pb
134.00
Nickel-Silver
Cu-Za-Ni
171.00
Alumel
Ni-Al-Mn-Si
203.00
Arsenic
As
214.00
Monel
Ni-Cu-Fe-Mn
256.00
Manganin
Cu-Mn-Ni
268.00
Constantan
Cu-Ni
270.00
Titanium
Ti
292.00
Chromel
Ni-Cr
427.00
Steel, manganese
Mn-C-Fe
427.00
Steel, Stainless
C-Cr-Ni-Fe
549.00
Chromax
Cr-Ni-Fe
610.00
Nichrome V
Ni-Cr
650.00
Tophet A
Ni--Cr
650.00
Nichrome
Ni-Fe-Cr
675.00
Kovar A
Ni-Co-Mn-Fe
1732.00



Neáu cuøng moät chaát lieäu, thieát dieän caøng nhoû hoaëc chieàu daøi daây loa caøng lôùn thì suy hao caøng lôùn.
Ñoàng thôøi trôû khaùng loa cao (8 Ohm) thì toång suy hao ñöôøng daây thaáp, ngöôïc laïi trôû khaùng loa thaáp (4 Ohm) thì toång suy hao ñöôøng daây seõ cao.

Baûng ñaùnh giaù suy hao ñöôøng daây vôùi AGW & ñoä daøi ñöôøng daây.


WIRE GAUGE (AWG)
LENGTH
IMPEDANCE
LOSS
18
25 ft        (7.62m)
4
12.94%
18
50 ft      (15.24m)
4
23.44%
18
100 ft    (30.48m)
4
39.33%
18
25 ft        (7.62m)
8
6.82%
18
50 ft      (15.24m)
8
12.94%
18
100 ft    (30.48m)
8
23.44%
16
25 ft        (7.62m)
4
8.41%
16
50 ft      (15.24m)
4
15.76%
16
100 ft    (30.48m)
4
27.98%
16
25 ft        (7.62m)
8
4.35%
16
50 ft      (15.24m)
8
8.41%
16
100 ft    (30.48m)
8
15.76%
14
25 ft        (7.62m)
4
5.39%
14
50 ft      (15.24m)
4
10.34%
14
100 ft    (30.48m)
4
19.10%
14
25 ft        (7.62m)
8
2.75%
14
50 ft      (15.24m)
8
5.39%
14
100 ft    (30.48m)
8
10.34%
12
25 ft        (7.62m)
4
3.29%
12
50 ft      (15.24m)
4
6.41%
12
100 ft    (30.48m)
4
12.21%
12
25 ft        (7.62m)
8
1.67%
12
50 ft      (15.24m)
8
3.29%
12
100 ft    (30.48m)
8
6.41%
10
25 ft        (7.62m)
4

10
50 ft      (15.24m)
4

10
100 ft    (30.48m)
4

10
25 ft        (7.62m)
8

10
50 ft      (15.24m)
8

10
100 ft    (30.48m)
8

8
25 ft        (7.62m)
4

8
50 ft      (15.24m)
4

8
100 ft    (30.48m)
4

8
25 ft        (7.62m)
8

8
50 ft      (15.24m)
8

8
100 ft    (30.48m)
8



Baûng so saùnh suy hao trôû khaùng loa & daây loa

theo bahung.com

Không có nhận xét nào:

Đăng nhận xét