Choosing your audio amplifier

[MrLuck]

Hi there,
I am quite new to working with the raspberry pi and doing these types of builds (mainly worked with more mechanical arduino projects before.) What I would like to know is how do you choose amplifier for your speaker. For example the PiGrrrl uses a 2.5W amp with an 8 ohm 0.5W speaker. Last I checked the speaker needs to be able to handle the amps output. At home right now I have a few extra 5V 3W stereo amps and a few 45ohm 0.3W speakers. Is it possible to use this combination? Or how do you properly choose an amp for your speakers for this project?

Thanks in advance

[tinkerBOY]

Most builders choose the PAM8403 stereo amp and a 1watt, 0.5watt, or 2watt all 8ohm speaker. I use these combinations all the time.

[MrLuck]

@tinkerBOY Do you mean one of these?


Because this is just the one that I got. Was just afraid of blowing out the speaker if I tested a 0.5w 8 ohm speaker with this amp without using a volume controller in between. But if this is what people usually use then awesome. Do someone know what the result would be if i reused a 0.5W 45ohm speaker, would that also be viable?

[tinkerBOY]

Yes. Take a look at this diagram, http://www.tinkerboy.xyz/wiring-guide-f ... ller-v1-1/

[MrLuck]

Okay thanks a bunch, what high/low pass filter have you used for the pwm audio in your projects? Or have you made one on your own?

[tinkerBOY]

The boards I'm selling already have low/high pass filters built in.

You can also build one yourself just follow the guide at https://sudomod.com/forum/viewtopic.php ... 33nf#p5061

[McGyver]

You can try your 45 Ohm speaker. Just take care to start with lowest setting on your potentiometer. It should work, maybe quite but you should be able to hear something. Try how it sounds and decide if you want to change to any other speaker. Do not aspect so much lower frequencies!

[NPlayer]

I'm having issues with that amplifier. I'm using a usb audio card connected to the audio pot, then to the amplifier. The output of the amplifier is connected to the 3.5 jack and the speaker (a game boy spare one) is connected to the 3.5 jack. Everything works as expected, but I've damaged two amps. The last one started to output intermitent sound, so I just wired the usb audio card directly to the output and everything started to work (just very quietly ).

The thing is that I don't know how I have to wire everything to prevent the amp failure. Do I have to use some resistors? The damage, could be cause by joining R & L at the speaker?

Any help would be appreciated, thanks!