This is a generic board from a speaker which has been botched, I'm trying to repair it as i do know it sounds a lot better than the ones you can buy cheap from lots of places! what i want to know is does it all look okay in terms of how everything is setup? it should be noted that a pam8403 is currently soldered to it, the board is about 10 years old if memory serves me right so excuse my terrible younger solder skills! should be noted as well i do intend on cleaning it all up as i know some traces are connected that shouldn't be! the issue was i connected a battery the wrong way round once upon a time 
I don't have a schematic so I'm having to guess everything here and just wanted a little guidance it does have a charger circuit as well as a pot, the pot is not connected nor battery!
Cheers guys
I don't have a schematic so I'm having to guess everything here and just wanted a little guidance
it does have a charger circuit as well as a pot, the pot is not connected nor battery!Cheers guys
Thanks i actually have done that, looking at the data sheet does give clues but there seems to be a lot of extra stuff that I'm trying to understand from this board, im unsure what it is that was done that produced such a better listening experience but i want to replicate it as the cheap pam8406s have zero base response and sound rubbish, this board on the other hand had a nice smooth tone with decent base.
I did think about getting something more powerful but i intend on having the board be powered by 18650s with only a usb to charge it, boost convertors unfortunately do not work and clip and cut out at high volume due to amp pull, this is something i do not know how to stop (my knowledge is limited and i am trying to learn!)
I know it can be done i just dont know how it is done.
I did think about getting something more powerful but i intend on having the board be powered by 18650s with only a usb to charge it, boost convertors unfortunately do not work and clip and cut out at high volume due to amp pull, this is something i do not know how to stop (my knowledge is limited and i am trying to learn!)
I know it can be done i just dont know how it is done.
Hmmm...
More batteries in series to raise potential (Volt)
12 or more Volt should produce the necessary headroom for a comfort listening. 5 V Is derivative from the mobile Cell phones & associates, that Need the 3.3V for logic.
12 V was popular for the old mobile, the car, and the output Power limit was quickly surpassed with the usage of boost converters, i.e. SMPS, inside the amplifiers.
More batteries in series to raise potential (Volt)
12 or more Volt should produce the necessary headroom for a comfort listening. 5 V Is derivative from the mobile Cell phones & associates, that Need the 3.3V for logic.
12 V was popular for the old mobile, the car, and the output Power limit was quickly surpassed with the usage of boost converters, i.e. SMPS, inside the amplifiers.
If you have bad bass response with this or another amplifier board , and you are sure that another board is playing ok , that not speakers fault , then you need to increase input capacitors capacity. Datasheet will tell you pins ,whose are inputs, and you can easily locate and try to connect similar ones in parallel and see if it makes any difference. Also , one of possiblity is that board have some kinda of tone control/bass boost circuit ,even passive , and that makes very big change in sound. Sometimes for small and weak speakers bass response at lower end is especially lowered , to limit frequencies , whose speaker can't withstand and play anyway. Thus more power left for upper bass .
I can confirm that I have actually fixed this amp I'm now in the process of replicating it in easyeda to add a proper charging circuit that has protection etc, just want to make sure I don't create a ground loop so I have been doing lots of research to understand PCB design better!
If I do succeed I will post an update! I am still wanting to create a more powerful speaker that's portable so i am still looking into how to do that but i guess i should start a new thread for that!
I'm now in the process of replicating it in easyeda to add a proper charging circuit that has protection etc, just want to make sure I don't create a ground loop so I have been doing lots of research to understand PCB design better!If I do succeed I will post an update! I am still wanting to create a more powerful speaker that's portable so i am still looking into how to do that but i guess i should start a new thread for that!
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