portable speaker project (tpa3118)

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so this is my portable bluetooth speaker project. i have had it for almost a year now and tried doing all kinds of mods on it and along the way learned a bit about electronics , since when i started doing this project i had no knowledge about electronics. now i have decided to build a second version of the speaker and do a youtube video tutorial on how it s made but before i do that i need to solve some problems with the speaker and maybe implement some other things into it.so i am hoping to get some opinions and ideas from people on this forum.

1).first problem on this speaker is the ground loop between the amplifier,preamplifier,bluetooth module since they are all running off the 12v battery and are connected with the audio signal wire.i tried using chep ground loop isolator from ebay 3 5mm Car RCA Amplifier Audio Noise Filter Ground Loop Isolator Suppressor Cgyg | eBay but this ground loop isolator only got me more noise maybe becasue it s not enclosed in any type of shielding , wrapping it in some aluminium foil might help ?

2).second thing to consider doing is modding the amplifier .the speaker is curently running tda8932 since i smoked the original tpa3118 when i was adding caps to it and accidently bridged chips ground with 24v rail.the mods i was planing to do on the tpa3118 are:
-adding more bulk capacitance on the power input
-adding on-off switch
-replacing 10uh inductors for 22uh inductors since i am running a 8ohm load

3). third thing i planed doing is to extend the L shaped bass reflex port. i just thought the longer the port the better but i don t know about the thicknes of the port . i don t know how to calculate the dimensions of the reflex port becasue i don t know the specs of the speaker and i don t want to change the size os the enclosure. the dimensions of the box are 32cmx22cmx16cm. can you even calculate dimensions of reflex port if you don t know the specs of the speakers ? also i thought of making the reflex ports on each side of the speaker like in picture below becasue that clears the top portion of the speaker for putting the handle,switches and potentiometers.and it would also look cooler in my opinion with the ports on each side of the speaker.

and thats about it for now if i remember anything else i will post here. some pictures of the speaker are down below all the help is appriciated :)


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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.