audio out put..

[Faisal_arr]

How could I calculate the audio out put from my mp3player ( in watts)

is it possible using multimiter.... or it is same in all mp3 player (if same caould any bdy tell me please)

thanx in advance...

 

[Nigel Goodwin]

To calculate power is VERY simple, you need to know any TWO of three things

Voltage
Current
Resistance

You can't measure it with a multimeter, an AC millivoltmeter or scope is required. But why would you want to know anyway?.

 

[audioguru]

If its output is designed for earphones then its max ouput power per channel is about only 0.05W.

 

[Jeg]

Υou can also try to find the specifications of your mp3 player on internet.

 

[Faisal_arr]

no name.... na serial no no model no .....
but i Connect it to my pc Speaker or some time in pc lINE IN IT works fine... what could be the outout watts .5 watts as audiogru mentioned .... And I wanted to know just to find a compatible and best supportes amplifier or GM for my car.....

 

[audioguru]

No, it does not have 0.5W output. It has only 0.05W output so it needs an amplifier to drive a speaker.

 

[Faisal_arr]

No, it does not have 0.5W output. It has only 0.05W output so it needs an amplifier to drive a speaker.

I mean it...

Ok if I make a low power amplifier using LM386 IC at the gain of 150 is the output will BE~7watts or less .....
I dont have the datasheet af this IC so Just wanna conform the the pin 4 & 8 are for gain control??

thanx 4 ur quik response

 

[audioguru]

Please don't talk about a power amplifier without looking in Google for its datasheet.
The LM386 is a small, low power amplifier for toys. With a 6V supply, its output into an 8 ohm speaker at clipping is only 200mW. With a 9V supply its output is 450mw. With a 12V supply it might melt while its output is 530mw. That is 1/2 Watt! About like a little clock radio.

Pins 1 and 8 on an LM386 are for gain control as shown on its datasheet.

An amplifier for 7W into 8 ohms will need a power supply voltage of about 25VDC. It will get hot and will dissipate about 6W so it would need a pretty big heatsink and a big power supply.

Gain is just sensitivity, not power. If you are listening to someone talking on a radio then they suddenly whispered, you turn up the gain to hear them at the same power as when they were talking.

 

[Sceadwian]

Actually, you could measure it with a multimeter, just output a 60hz sine wave on the mp3 player and measure the voltage on the meter in AC volts. Use the resistive load of the headphones to come up with a rough idea of the actual power out. I don't know how common DC output stages are with MP3 players but if it's not DC coupled then you'd need to scale up the calculated power ouput at 60hz against the exponential curve of the output capacitor's rateing compared to the average frequency of a complex waveform, not easy or reliable, but possible.