Speaker Amplifier circuit problem

[FredSS]

Hello everyone,

I have to design a speaker amplifier circuit. We are told the impedance of the speakers and the minimum voltage they require and also the voltage source. After researching I have found that the LM386N-4 is a popular choice. According to a datasheet of LM386N-4 - https://www.icrfq.com/part/2377557-LM386N_4.html. I've seen many circuit diagrams but what I don't understand is how to pick the voltage gain needed for the amplifier.

I originally thought that you would need to know the input audio signal voltage and when you multiplied that by the gain that would need to give the minimum voltage required by the speaker, but it appears that what matters is the current which I don't get.

And are you able to design such a circuit without knowing about the audio input signal? If you do need to know about it, what is it you need to know about it and why?

I would be very thankful for any help as I am very lost.

Thanks in advance.

 

[GoldenVulture]

Re: Speaker Amplifier circuit problem

I would be very thankful for any help as I am very lost

I'll send out a search party..... Hang on there !!!!

 

[Darg1911]

Re: Speaker Amplifier circuit problem

Not again ...

 

[FredSS]

Re: Speaker Amplifier circuit problem

Thanks for your reply!

 

[GoldenVulture]

Re: Speaker Amplifier circuit problem

:chairfall

 

[Joey Voltage]

Re: Speaker Amplifier circuit problem

If you are asking these questions, you have a lot of reading to do before designing any amplifier. IMHO Your questions are too wide in scope, and would required too big of a write up to interest anybody here to do so. I would encourage you to check out this site below. It is written for exactly the purpose of your inquiry. The extensive library of articles will answer your questions, and set you on the right path of consumer and hi-fi audio design. http://sound.whsites.net/articles.htm