Guys! please! I really need a return here.
The power supply of my Creative A520 speaker system got nuked in lightning. I tried an external adapter 12V/1Amp and it works with occasional volume loss during heavy bass. I guess the adapter is unable to supply enough current.
I am trying to repair the power supply but cannot figure out the values of the burnt parts.
I can see two resistors and a zener diode as burnt:
Please help me figure it out.View attachment 94210
Hi xTatshx,I' ve used 12Vdc 5Amp SMPS(Commonly found on CCTV systems) to supply the Unit and It sounds Fine without cracking the sound, even i Tune to its maximum Volume no cut offs.
That would require the amps to be 100% efficient and no other power overheads?? Surely figures like that are only used in dodgy advertisingThen a 12V power supply should be rated for 30/12= 2.5A.
Sure. No problem, but just checking if the DC output from the power supply into the amplifier circuit enters through a full wave bridge rectifier (W10 in my case) for a typical surround/sub woofer system.[I don't have that speaker system so cannot help with internal wiring, sorry].
Except it's not - the made up specification might 'claim' such imaginary values, but it's certainly not 'rated' at thatI have a similar Sylvania sound system as this Creative one. Its woofer is the same size but it has only two satellite speakers, not 5 of them. It is rated total output power is 150 Watts or 75W RMS.
Thanks for your reply audioguru. Few more clarifications.A few amplifiers are "class-A" and are actually room heaters and they draw maximum power supply current all the time. The Creative amplifiers and most other amplifiers are class-AB or class-D that draw only as much current as the output power needs. Your Creative speaker system is rated at 37 Whats when it is blasting severe distortion louder that it can play normally. That is 37/12= 3.1A. It would draw 0.3A when not playing loudly.
We do not know what is causing your static noise or if it will happen again.
It sounds like your bass control is worn out and needs a replacement. The small woofer and low amplifier power does not produce much bass anyway.