The CA-TB21H is a 2.1 channel Class D amplifier module built on the TPA3116 chip, delivering 50W + 50W for the left and right channels plus 100W for the subwoofer channel from a DC 12–24V supply. Audio sources are covered by Bluetooth 5.1, AUX line input, USB / TF card playback and the included IR remote, while the BT-APP provides EQ and light-effect control from a phone. A gold-fin heat sink, five front control knobs and expansion ports for a microphone preamp board make this board ready for OEM speaker systems, home audio kits and audio equipment assembly lines.

• 2.1 channel output: left and right 50W each plus 100W subwoofer, TPA3116 chip, 20Hz–20KHz frequency response.
• Four input methods: Bluetooth 5.1 (BT-APP, 10m open area), AUX, USB / TF card, and IR remote control with button battery.
• Five front knobs: master volume / power, treble, bass, subwoofer frequency (20–200Hz) and subwoofer volume, plus independent L/R channel volume.
• APP control: BT-APP supports EQ adjustment, local media, USB drive, SD card, light effects and find-my-device functions.
• Expansion ready: MIC preamp reverb input and output ports, subwoofer line-level output for an external pure power amplifier board.
• Bridgeable mono: set DIP switch 1 to ON (PBTL) to bridge the two channels into mono for one high power speaker.
• Five-fold protection: reverse polarity, under-voltage, over-heat, over-current and short circuit protection.

Subwoofer and left / right channel speaker terminals, flexible Bluetooth antenna, USB port, AUX audio input and DC 12–24V power input (5.5 x 2.1mm DC plug) are arranged on one edge, so the board can be assembled into a housing without extra wiring harnesses. A power status LED and the five knobs sit on the front panel.

Output power rises with supply voltage and falls with speaker impedance. The reference figures below are measured with 4 Ohm and 8 Ohm loads at 19V and 24V, which helps you match the adapter to the actual speaker set.

For a balanced 2.1 system we recommend a 24V 5A or 8A DC adapter, 4 Ohm 30–50W left and right speakers and a 4 Ohm 60–100W subwoofer. A higher current adapter keeps the 100W subwoofer channel stable at high volume, and the adapter power should always be higher than the actual working power of the board.

Before fitting the knob, turn the potentiometer along the pointer direction to the left until it reaches the minimum and cannot rotate further. The horizontal line on the knob should then face the direction shown in the diagram, so the volume scale matches the actual position.

For bridging to mono, power off first and set DIP switch 1 to ON (PBTL function). Connect only one speaker on either side; when connecting two speakers, each must be 4 Ohm or higher and the parallel impedance must not go below 2 Ohm. Expansion port 1 is the mic preamp reverb input and expansion port 2 is the reverb output, and the subwoofer line-level output can feed an external pure power amplifier board.

Install the BT-APP, switch off phone Bluetooth, power on the module and connect the device named BT-APP (the BT-APP-BLE entry is not used by the APP). The APP provides EQ adjustment, local media playback, USB drive and SD card browsing, light effects and find-my-device. EQ curves apply while the APP is connected; bass and treble are adjustable.

The package includes an IR remote with button battery and insulation sheet: power, mode, mute, play / pause, previous / next, EQ, volume up and down, single / all repeat, USB / TF card switch and 0–9 track selection. Working range is about 7m in line of sight and narrows at a 15 degree angle.

Suited to audio equipment manufacturers, speaker system assembly plants, audio electronics distributors, OEM and ODM product developers, private label speaker brands, custom packaging projects and regular bulk purchasing teams. Typical use cases include 2.1 home audio systems, bookshelf and subwoofer sets, shop background music, DIY amplifier kits and karaoke speaker boxes.

Comprehensive OEM and ODM support covers custom logo, PCB color, packaging, function tuning and 7-day sampling, so the same board can be delivered in your own brand and configuration for different markets.

Each board is packed in an individual box of 11 x 11 x 5cm with a gross weight of 0.3kg, protected by shock-proof foam and shipped in export-grade cartons. A printed user manual is included in the box; OEM branding, custom packaging and mixed container loading are available.

Direct factory supply of audio amplifier modules with cross-border export experience, verified supplier with OEM / ODM customization, stable output and short lead time for repeat orders. Send us your target market, speaker configuration and order quantity to get a quotation and sample arrangement.

Contact us now for wholesale price, OEM customization and samples.