DIY: Upgrade Marley EM-JA006SB Speaker

Marley EM-JA006SB speaker review: appearance is great, and the sound quality is good, but the external AUX and power cables are lacking. How can we improve this? If you're interested, keep reading.

I. Solution:

Recovery from the internal circuit board is impossible. However, you can add a module. Here’s the plan: (Note that ground interference issues are not considered here, so DC isolation will need to be added later.)

II. Wiring – Power Board:

From the original power board, extend the USB, power, and AUX cables. There’s also an indicator light on the back; if it lights up, add a resistor (1K) across the positive and negative terminals to ensure it lights up when the power is plugged in.

III. Wiring – Decoder Board:

Choose a 12V decoder board with USB, AUX, and Bluetooth 5.0. Remove the USB female port and the three buttons. Route the AUX and USB ports to the speaker’s internal power board. Remove the TF card function. Connect the three buttons to the speaker’s built-in controls: Previous Track/Volume Down (to speaker -), Next Track/Volume Up (to speaker +), and Play/Pause/Mode Switch (to Bluetooth icon). {After testing, the decoder board and speaker controls share a ground connection, so each button needs one wire plus one ground wire.}

IV. Wiring – Switches:

Use a single-pole double-throw switch module to control both the decoder board module and the original speaker power. Since the two voltages are different, choose a switch that disconnects the negative line to cut off both parts. A recommended switch module is SRD-12VDC-SL-C SONGLB, with external connections for the button and indicator light. Attach a small indicator light next to the switch button to show its status. 

*Note: As this is the final step, ensure you disconnect the switch from other buttons during the external wiring process to avoid ground interference issues.

V. Wiring – Isolation Power Supply:

Without an isolation power supply, there’s some noise when powered on, though music still plays. Use a separate power supply for the decoder board to eliminate noise. Prepare a 12V DC isolation power supply like the B1212S-2W2. After testing, it outputs 13.5V with no load. If the load is too low, connect a resistor to the output to stabilize it, aiming for around 12V. Adding a load resistor (200-500 ohms) will adjust the voltage to about 12V.

VI. Completion:

Secure all modules with hot glue before assembly. Tidy up the wires and close it up.