ไม่ค่อยมีใครพูดถึงเรื่องกระแสมากนัก เพราะใช้ Adapter Com กัน แนวคิดจากผู้ออกแบบ
"I addressed this by choosing a commercially available switching supply of the type you routinely see powering up your portable computer. There are literally tons of surplus supplies available for this purpose, providing regulated 19 volts DC at more than 2 amps or so on their output and having their input going safely to the wall AC power outlet through a safety approved power cord. These supplies are isolated for shock safety and are also short-protected. At 19 volts output they do not represent much of a hazard to humans.
What? An audiophile component with a switching power supply? Get over it ? it works fine."? Nelson Pass 2012
http://www.diyaudio.com/forums/diyaudio-com-articles/214808-amp-camp-amp-1-a.html'' Your calculations would be correct if Q2 was a constant current source, but it's not.
Note how C2 is connected to the bottom of R3/R4. When Q1 increases it's current to pull the load negative, the voltage drop across R3/R4 increases, C2 couples this change to the gate of Q2 making it conduct less. Q3 also conducts more which reduces the Q2 gate voltage. When Q1 reduces current, the voltage drop across R3/R4 reduces. C2 couples this positive going voltage to the gate of Q2 making it conduct more. Q3 also sees this voltage drop, it conducts less until the current flow through R1/R2 and to the load increases to makeup the difference in voltage from the source of Q2 to the drain of Q1.
If Q2 was a constant current source and the bias was 1 Amp, Q1's current could go up to 2 Amps or down to zero Amps supplying +/- 1 Amp peak to the load. Because Q2's current changes to be the opposite of Q1, the load current could be +/- 2 Amps in theory. However, Q1 would be very non-linear, although distortion would be mostly even order. In this design, with an 8 ohm load, the amp runs out of voltage before it reaches +/- 2 Amps load current. Idle current could be reduced, but distortion would increase. " Loudthud
http://www.diyaudio.com/forums/pass-labs/215392-amp-camp-amp-aca-24.htmlจัดให้ข้างละ >2 Amp ครับ ตามกำลัง ผมไปเช็คของผมก่อนทำไมไม่กินกระแส ต้องมีอะไรลากลับบ้านสักตัว 2 ตัว 3-2-1-raccoon
