Choosing a Bluetooth module

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I'm trying to pick a Bluetooth module to use in a portable speaker. Looking at a few things available on aliexpress.

Bluetooth Stereo Audio Modules Modification Wireless Speaker Amplifier Audio KRC-86B V4.0 DIY Module
Bluetooth Stereo Audio Modules Modification Wireless Speaker Amplifier Audio KRC 86B V4.0 DIY Module-in Other Electronic Components from Electronic Components & Supplies on Aliexpress.com | Alibaba Group

Has anyone used the one linked above?

This one: New XS3868 Bluetooth Stereo Audio Module OVC3860 Supports A2DP AVRCP Good
New XS3868 Bluetooth Stereo Audio Module OVC3860 Supports A2DP AVRCP Good-in Other Electronic Components from Electronic Components & Supplies on Aliexpress.com | Alibaba Group

Shows up often, but it looks like it has differential outputs L+, L-, R+, R-. That would definitely complicate things. I'm using a class d amp with single ended input.

I guess another option would be to get a cheap usb-chargeable Bluetooth receiver in a case with 3.5mm output like this: Universal 3.5mm Car Bluetooth Audio Music Receiver Adapter Auto AUX Streaming A2DP Kit for Speaker Headphone
Universal 3.5mm Car Bluetooth Audio Music Receiver Adapter Auto AUX Streaming A2DP Kit for Speaker Headphone-in Speakers from Consumer Electronics on Aliexpress.com | Alibaba Group
and take it apart for the pcb. Any thoughts?

In case it makes any difference I'm using 7.4v li ion to power the amp and will use 5v ldo to drop the voltage down for the Bluetooth module.
 
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Shows up often, but it looks like it has differential outputs L+, L-, R+, R-. That would definitely complicate things. I'm using a class d amp with single ended input.

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In case it makes any difference I'm using 7.4v li ion to power the amp and will use 5v ldo to drop the voltage down for the Bluetooth module.

Hi, I skipped the very object of the thread :p
Those L+, L-, R+, R- seem to me to be the classic single ended topology, otherwise a GND reference would be mentioned.

For the 5V supply, probably a resistor and Zener diode would suffice
 
I have the XS3868. You can use L+, R+ and Gnd but I think that's the reason for the noise everyone is getting. It's also very difficult to make connections without a breakout board. Many people are using this USB Bluetooth receiver. It's cheap and easy. I also like the idea of the panels that support BT, Micro SD, USB and even FM. You have all the buttons neatly placed on one easy to mount panel. I passed on it at the time because I couldn't find one that was confirmed to operate from 3.7V.

I'd love to see more details on your build. Most people say it's not worth the money and time spent but it was a fun and learning experience for me. Most of my parts were re-purposed from something else.
 
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