Question Audo Amp Help

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I'm finishing up my first portable, but I'm having trouble with the audio. Without an amp it is way too quite to play, I picked up an audio amp off ebay but it makes a weird buzzing/pulsing noise and its way too loud.
I'm wondering if there's a way to lower its power to make it sound better, or if there's something better I should be using?


SEGA Radica portable
Mono sound
The amp I got -> http://www.ebay.ca/itm/191921396767?_trksid=p2060353.m2749.l2649&ssPageName=STRK:MEBIDX:IT
Useing 5v power
 
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What speaker are you using? That can have an effect on the perceived audio output quality of your amp. You need to try to match up the wattage of your amp with the wattage of your speakers, for one.

According to the datasheet of the LM386, (www.ti.com/lit/ds/symlink/lm386.pdf) you'll want a speaker with an impedance of for maximum power output. However, with an input voltage of 6V, you'll only be able to be able to get a power output of about a .325W. (A 4Ω, 1W speaker seems best here.)

According to this logic, your amp shouldn't be outputting enough power to make your speakers sound noisy and gross. SO, you need to adjust the "volume control" knob on the amp. That dial controls the "gain", measured in decibels. When you crank that thing up all the way, it makes not just the Sonic music loud, but also the static interference and electronic noise your amp and electronics create, hence the buzzing noise.

tl;dr: Your gain is probably set too high. Turn the knob slowly until your speaker sounds better. You may have to change out your speakers if they're not rated for the amp properly.
 
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Hmm I see. That makes a bit more sense. Thanks! :D
I was useing a 4Ω 3W, and whatever speaker normally comes with the GameGear. I'll try to find myself a 4Ω 1W speaker and see if that helps!

I was able to get it at a good volume (still with noise) if i turned the knob slowly, but I also want to easily be able to control the volume. Would I be able to limit this with a resistor connected to the pot?
 
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The easiest way that I know of to control volume output is to connect a 1kΩ potentiomenter on the output of your audio amp. Google a basic potentiometer circuit if you don't know how pots get wired up.
 
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Looks like I cant find any 4Ω 1W speaker's that will fit into my case. So I suppose I'll have to look into getting a new audio amp instead.
 
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