Ðề: Thắc mắc về loa 4 ôm và 6 ôm!
Hon tram tra loi ve van de nay, toi khong co doc het. Tuy nhien, cac loa dieu duoc che tao theo nhu cau nhu sau:
a. cho nha, cac phong tra, hop dem,... nguon dien la 110/220 V co kha nang phat manh, loa thong dung la 8 ohm
b. cho xe hoi, nguon dien la 12 Vdc, loa thong dung la 4 ohm
c. cho lo tai, nguon dien tu pin, thong thuong la 3.3 V, cac earphone duoc che tao tu 300 - 600 ohm: tranh co nguoi nge bi vo mang nhi. Cac hang xuong co the bi pha xan neu san pham cua ho lam hai toi gioi tieu thu
d. loa bo. They la nhung bo loa nho cho may vi tinh va tv, de choi game hay la coi phim. Da so, day la loai loa " TE HAI NHAT", tai sao?
d1. choi chu. 100 W khong co nghia la 100 W cong xuat.
The nay: 1 cuc ampli to bo boi yamaha/sony/... phat 70 W x5
1 bo loa cung voi cai ampli mong hon cai mai DVD, ... duoc quang cao la 75 W X5
1 bo loa 3 mieng nho cho may vi tinh,.. duoc quang co la 380 W
Thi du #1, nang xuat duoc tinh theo don vi trung binh (rms-root mean square).
Thi du #2, nang xuat duoc tinh theo don vi cao nhat (p-p -peak to peak).
Thi du #3, nang xuat duoc tinh theo cong thuc tau lau, co troi moi hieu duoc
Luat cua thien nhien va nang xuat dien, trong cung mot khung canh, dung tich co anh huong rat la quang trong voi nang xuat. Co nghia la, mot su quang co khong ro rang de lua gioi tieu thu.
The nao la loa hay?
- phat ra duoc am thanh deu dang, tu am thanh tram thap toi am thanh cao vut.
de phat duoc am thanh tram thap, the tich cua loa phai lon, va thung loa cong phai lon, dong thoi phai nang de loa khoi bi rung
de phat duoc am thanh cao, trong treo, loa khong can lon
de phat duoc am thanh trung, loa vua phai
3 cai loa trong mot thung duoc goi la 3 chieu (3 way)
De duoc gon va hay, thong thuong la loai loa 3 mieng: trai, phai, va 1 thung bass
Mot bo loa hay, khi mo am thanh that nho, cac ban co the thuong thuc duoc tung tieng nhac. Khi am thanh mo lon, tieng van trong tung not nhac, va khong bi re.
NEN CHON 2, 4, 6, 8, 16 ohm loa?
16 ohm chi co cac chuong trinh dai nhac hoi dung (khong han)
dai da so, chung ta nen dung 8 ohm: nang xuat cua loa "PHAI" cao hon nang xuat cua ampli, neu khong, chay loa. Trong luc loa chay, dien tro trong loa co the xuong toi 0, dan toi chay ampli. Mot khi loa chay roi, dien tro se len rat la cao, ko so ampli bi chay nua ( hu hu, chay rui, con dau ma chay nua)
2 ohm duoc dung cho xe, chi la cho bass (am thanh that la tram)
Su phan phoi am thanh cua bo loa 5.1:
Loa giua, am thanh cua tieng noi dien thoai. Day la tang song cua am thanh ma nguoi ta phat ra va nhan nghe duoc ro rang, trung binh tu 500 to 5000 (hezt) tan so moi giay. Trong 5.1, loa nay nhan toi 70% cua am thanh. Nghe nhac ma xai 5.1 la mat me (xin loi) am thanh stereo dui!!!!
Duong nhien, phan con lai, 30% se duoc phan phoi qua 4 loa con lai.
Loa .1 chinh la cai thung bu nhat do. No cat nhung am thanh tram thap, thong thuong tu 180 (hezt) tan so tro suong, trai + phai. Boi vi lang song thap, cac ban rat kho la phan biet duoc am thanh phat ra tu huong nao. De duoi gam giuong, duoi ban viet, hay la trong mot goc nha roi de chau bong len cho vui.
Am thanh noi? Nghe nhac thuan tuy, am thanh noi lam chua (ko ngot) tieng nhac, theoy kien cua minh.
Chon ampli: 1st: tieng re thap (.007% distorsion)
2nd: hang che tao: Hang Noi Tieng se dung don vi chinh de do am thanh
(nang xuat voi don vi rms - mean root square)
digital in/out : chat luong am thanh ko bi giam tu cd/dvd qua ampli
(coaxial cable vs optical? ma vang hay ko?
ha ha. Duong day chi co 1 metta, chi co nhung day so 00011000
day 50 nghin nghe nhu day 1 trieu
Day gi? Day la loai day hinh (mau vang) ma cac bac thuong gan tu dvd toi tv. Tai sao? Soi o giua duoc boc boi soi ben ngoai (shield), ko phai la 2 soi day song song voi nhau.
Mot it khai niem ve loa cho anh chi em. Minh o nuoc ngoai, Ko quen danh dau, dung tieng viet ko ranh. Anh em nao co nha tam, danh dau va dung tu ngu quoc noi de de hieu.
Chuc anh chi vui ve