ZK-AS21 TPA3255 Bluetooth 5.1 Power Amplifier Board – Hi-Fi 2.1 Channel 220W x 2 + 350W Digital Audio Receiver with Treble, Bass, and Subwoofer Frequency Control

Parameter	Detailed Specification
Model	ZK-AS21
Amplifier Chip	TPA3255 (Dual High-Performance Class D)
Channels	2.1 Channels (Left + Right + Subwoofer)
Power Output (L/R)	≤ 220W per channel
Power Output (Sub)	≤ 350W
Bluetooth Version	5.1 (Transmission distance: up to 15m)
Audio Inputs	Bluetooth, AUX, USB Disk, USB Sound Card
Supply Voltage	DC 12V – 38V (Recommended: DC 36V, ≥10A)
Speaker Impedance	L/R: 3-8Ω, Subwoofer: 2-8Ω
Dimensions	141mm x 131mm x 27mm

Price

🚚 Ships within 24 Hours
📦 Pan India Delivery

₹ 2,838.98

(Tax included)

बारकोड: 43457675

Product Description

Experience true Hi-Fi performance with the ZK-AS21 TPA3255 Bluetooth 5.1 Power Amplifier Board. This 2.1 channel digital powerhouse utilizes dual TPA3255 chips to deliver a massive 220W per stereo channel and a dedicated 350W output for your subwoofer. At Robogears, we recommend the ZK-AS21 for its exceptional clarity and ultra-low distortion across the entire audio band. Unlike basic amplifiers, this board offers independent tuning for treble and bass, along with a dedicated crossover frequency control (20-200Hz) for the subwoofer. Equipped with Bluetooth 5.1, AUX, and USB inputs, it is a versatile solution for DIY speaker builds and home theater upgrades. The built-in silent cooling fan and robust protection circuitry ensure that your system remains cool and safe even during high-power marathon listening sessions at your Pimpri facility.

Detailed Key Features

Massive 2.1 Channel Output: Delivers high-definition sound with 220W for left and right speakers plus 350W for a deep, cinematic subwoofer experience.
Precision TPA3255 Architecture: Features high-performance Class D efficiency with integrated feedback and error correction for crystal-clear, audiophile-grade audio.
Comprehensive Sound Control: Equipped with six low-noise preamplifiers (30dB gain) and dedicated knobs for main volume, L/R treble/bass, and subwoofer frequency/volume.
Versatile Connectivity: Supports high-speed Bluetooth 5.1 for wireless streaming, alongside traditional AUX, USB disk playback, and USB sound card modes.
Intelligent App Integration: Compatible with the "Wuzhi Audio" APP to customize Bluetooth names, set passwords, adjust sound effects (10-segment EQ), and manage playlists.

All Technical Details

Mechanical Power Switch: Features a quick-response mechanical switch for instant power-off without the need for long-pressing.
Stepless Tuning: Utilizes a high-end rotary encoder for smooth, infinite volume adjustment rather than discrete digital steps.
Safety Protection: Multi-stage safeguards include anti-reverse connection, undervoltage, overheating, overcurrent, and short-circuit protection with automatic recovery.
Build Quality: Constructed with an anti-static PCB and a protective shell to ensure durability during assembly and long-term use.

Prototyping & Engineering Tips (Robogears Exclusive)

Power Supply Matching: For maximum performance at your Pimpri workshop, we highly recommend a high-current power supply (e.g., 36V 10A or higher). A weak power supply will cause the sound to clip or the board to reboot during heavy bass peaks.
Cooling Clearance: While the board has a built-in silent fan, ensure your custom enclosure has adequate air vents. Blocking the intake will lead to thermal throttling, especially when driving low-impedance 2Ω or 4Ω loads.
Wiring Caution: The speaker terminals are spaced closely. Ensure no stray wire strands cross between terminals to prevent short circuits. Always make wiring adjustments while the power is completely disconnected.
Subwoofer Tuning: Use the "Subwoofer Freq" knob to set the crossover point. If your main speakers are small, set the frequency higher (approx. 120-150Hz). For large floor-standing speakers, lower the frequency to 80Hz for a more seamless blend.

Package Includes

1 x ZK-AS21 TPA3255 Bluetooth 5.1 Power Amplifier Board
1 x Protective Shell Set (Mounting Columns & Screws)
1 x Screwdriver for Assembly
5 x Aluminum Control Knobs

Image Disclaimer

Product images are shown for illustrative purposes only. The design of the heatsink or the branding on the PCB may vary slightly between production batches, but the TPA3255 technical specifications and 220W*2+350W power rating remain as described.

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