Intermediate

Class-D Stereo Amp Board

Wire a 12-24 V class-D amplifier module with a protected DC input, controlled audio input, speaker output checks, and heat/current tests.

Safety first, always.

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Bigger audio module build

Wire a 12-24 V class-D amplifier board with input control, fuse, speaker outputs, and first-power checks.

Bench time

2-4 hours

Typical parts

$40-$100 AUD

Power

Approved 12-24 V DC adapter

You finish with

Low-voltage stereo speaker amplifier

Before the first wire

Know the build before you power it.

Use a DC adapter with current rating that matches the amplifier board and speakers.

Do not power this from a car battery for a first build; a current-limited bench supply is kinder while testing.

Class-D speaker outputs may be bridge-tied. Do not join speaker negatives together unless the board manual says so.

Start with cheap test speakers before connecting anything valuable.

Bill of materials

8 parts groups to gather

Check every spec

Qty	Part	Exact spec	What it does	Inspect before use
1	TPA3116 or similar class-D amp board	12-24 V DC, stereo, documented speaker output labels	Drives speakers efficiently from a DC supply.	Find PVCC/VCC, GND, L/R input, and each speaker terminal.
1	Approved DC adapter	12-24 V, current rated for board	Provides isolated power.	Voltage and polarity match the board.
1	Input fuse	Sized above normal current but below wire rating	Protects wiring during faults.	Fuse sits close to the DC input positive.
1	Power switch	DC-rated above adapter current	Turns the amplifier on cleanly.	Switch only the positive feed.
1	Audio input socket or Bluetooth receiver	Line-level stereo output	Feeds music into the board.	Left, right, and signal ground are clearly labelled.
1	Volume potentiometer	10-50 kohm stereo audio taper or board-mounted control	Controls line signal before the amp.	Wipers move smoothly and both channels match.
2	Speakers	4-8 ohm, wattage suitable for board	Convert output power to sound.	DC resistance is sensible and cones move freely.
As needed	Speaker wire and enclosure	Twisted speaker pairs, insulated terminals	Keeps output current away from the input wiring.	No loose strands at the amp terminals.

Build boundary

This is for low-voltage DC amplifier modules. It does not cover mains amplifier internals, valve/tube amps, car battery installs, or high-power PA wiring.

Part modules vary. Read the markings and datasheet for the exact board in front of you before applying power.