Active Speaker

1. The Enclosure: From Passive to Active

In August 2024, I transformed an old passive Samsung subwoofer into a modern active speaker. The enclosure featured a "hollow" rear zone structurally separated from the acoustic chamber, which was the perfect place to install electronics without disrupting the sound. I utilized the factory plastic standoffs to securely mount the new boards.

2. Electronics: The "Ironing Method"

Unlike my previous photoresist projects, I experimented with the Toner Transfer method ("ironing") to fabricate the PCBs.

• Amplifier: A custom mono stage delivering 20-30W, equipped with a massive heatsink for passive cooling.
• Power Supply: A filtering block with a bridge rectifier (S4VB) and quality Marcon electrolytic capacitors (4700uF / 35V), powered by a reliable LAPP AG transformer to ensure hum-free operation.

3. Modern Interface and Assembly

To add modern functionality, I integrated a multi-functional module (JQ-D106BT-A1) which adds:

• Bluetooth Connectivity
• FM Radio (with an internal antenna routed discreetly)
• USB & TF Card Slots
• AUX Input

4. Cable Management

I paid special attention to the wiring. All cables are twisted to reduce electromagnetic interference and tidied up with zip ties. The control panel, power jack, and fuse were fitted into custom-cut holes, resulting in a clean, factory-like finish.