Hi,
I use these pre-made modules to record 4 minute sound files (recorded through the built in microphone by pressing the red button), however i would prefer to directly transfer the sound file to the pcb to improve the sound quality. I can’t find a pre-made board that has this feature, so any suggestions on adapting this board or other ideas would be greatly appreciated.
Many thanks in advance.

 

Do you mean transferring to a PC or laptop?

 

Hi,
Yes, sorry for not clarifying. I would like to directly transfer an mp3 file from my laptop to the circuit board.
Many thanks

 

There is This module from Adafruit. You will need to convert the mp3 files to OGG before transferring though.

 

Did you mean record the audio out from the PC to your sound module not using the on board microphone?

 

Yes, that’s correct

 

OK. It is possible to modify that module. I have one similar I can look into later today.
Do you have schematic of this module?

 

Thanks so much for your help. I’m afraid I don’t have a schematic for it, sorry.

 

Remove the microphone and inject the sound signal there.
AC couple the signal in. You will have to experiment with the signal amplitude.

The COB circuit probably looks something like this.

 

And if you need sound effects, look here:

https://www.myinstants.com/en/categories/sound effects/

 

Thanks so much for your help. I’m afraid I don’t have a schematic for it, sorry.

As MrChips suggested remove the mic element.
The board below is not exactly the same as your module but uses the same components, so makes a good reference.
The simplest solution is to connect a 100nf cap to the mic + input to use as a new input from the PC as shown below.
The audio out from the PC will need to be reduced and hopefully that can be controlled by the PC or will need to add an attenuation circuit.

 

Thank you both so much for your time and help, your advice is greatly appreciated.

Would there be any way to connect a micro usb to the board to enable me to transfer the audio file from my pc, or would that be asking way too much from this pre-made pcb?
Many thanks!

 

I don't see how as that sound module is analog input only via the microphone input.

 

Ok, I shall remove the microphone and give that a try. Thank you both so much for your help!