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HI,
yes, i also tried, but the resistor makes the output sound even lower wich makes the maximum volume very low...
Meanwhile i started searching for the other two options. I couldnt find any isolation inverter like you said (isolation transformer) for such low values. i find a lot with 5v...
it didnt work :/ im using tl072cp. actually it got lower but because the overall output sound also got lower but the same "bad sound" effect there. i also changed the inputs..
Hi,
I've made a small schematic to make sure i got it.
now the same circuit for the right amplifier input. this way signal ground pin from amplifier is not connected. am i missing something? feel free to complete the schematic.
after many time of searching and trying to do it following your instructions i got really confused.
this is the configuration you are talking about right? can you help with values?
i will need 2 channel opamp right?
edit: if i understood right is to use an opamp to connect the output signlas of bluetooth to the amplifier inputs, yes?
im sorry for the missunderstanding, what i meant was the bad sound stops (data sound).
i cant power bluetooth with 5v, maybe u mean amplifier?
i was reading a bit meanwhile 2 audio transformers you mean like ground loop isolators right?(between bluetooth module and amplifier)
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both work perfectly by their own, the issue is on the interconnection.
the "ch" sound i fixed by using 100 ohm resistor on L+ and R+ amplifier output. with 50 ohm i still ear it so between theese values i should find the best option.
i've tried both options and it doesnt work quite well. the...
first thing, im always testing on lipo batteries. the only difference is using 1 for both modules or 2 (one for each). im not using anything lse but lipo battery.
yes i tried it. only with bluetooth module operating with earphones/speakers it works perfectly.
using only amplifier direct to...
thanks for the reply, i've tried that and no effect.
with two diferent power supplies (both lipo) the "data sound" stops completely and just a small "ch" sound remains. but, for some reason, when using two diferent power supplies the sound stutters. with the 4 caps it just makes it lower but...
Hi all,
Im using a pam8403 2x3w module audio amplifier and BLK-MD-SPK-B bluetooth module receiver (datasheet here). for this thread sake i've made a simple schematic to show you the problem im having. last time i built this schematic (last summer) this noise was not ocurring.
I've been...
Ok thanks a lot, ill give it a go...
I tried at the output and it worked. I tried with and without capacitors and its easy to notice the diference in sound quality
Im using MCP73831 as Li-Po charger and actually it has "Integrated System Load Sharing and Battery Charge Management". And the way you are saying a parallel configuration would be enough, something like this below?
it seems a litle bit inneficient since usb already has the 5v i need for the...
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