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Electronics, sensors, robotics kits, PC components, peripherals — everything Unik Systems carries, in one place.
BenQ MOBIUZ EX271 27-Inch QHD 180Hz Fast IPS Gaming Monitor
[Monitor] BenQ MOBIUZ EX271 27-Inch QHD 180Hz Fast IPS Gaming Monitor Level up your gaming experience with 2560 x 1440 QHD resolution, 180Hz refresh rate, 1ms MPRT response time, and AMD FreeSync Premium. Features HDRi intelligent auto-brightness tuning and built-in 2.1 channel treVolo sound with integrated subwoofer. ⭐ Key Features - 27" QHD (2560 x 1440) Fast IPS panel - Ultra-smooth 180Hz refresh rate with 1ms MPRT - Proprietary HDRi technology optimizes HDR images based on room lighting - 2.1 channel treVolo speakers with 5W woofer and custom audio modes - Light Tuner with 20 color level adjustments to spot hidden enemies 📋 Technical Specifications - Panel: 27" Fast IPS - Refresh Rate: 180Hz - Response Time: 1ms (MPRT) / 2ms (GtG) - FreeSync: AMD FreeSync Premium - Video Ports: 2x HDMI 2.0, 1x DisplayPort 1.4 📦 Package Includes - 1 x BenQ MOBIUZ EX271 Gaming Monitor - 1 x Ergonomic Tilt/Swivel Stand, DP Cable, Power Cable
Passive Radiator Bass Diaphragm Rubber Speaker Vibration Plate for DIY Speakers
[Passive Radiator] 🔊 Oval, Square & Round Passive Radiator Bass Diaphragm Rubber Speaker Vibration Plate for DIY Speakers Deep Bass Enhancement • Passive Design • No External Power Required • Ideal for DIY Speaker Projects The Rubber Passive Radiator Bass Diaphragm is a high-quality auxiliary bass vibration plate designed to significantly improve the low-frequency response of speaker systems. Available in Oval, Square, and Round shapes with multiple sizes, this passive radiator enhances bass performance without requiring additional power or amplifier channels. Unlike conventional speakers, a passive radiator does not contain a voice coil or magnet. Instead, it utilizes the air pressure generated by the active speaker driver to vibrate, producing deeper, richer bass while minimizing distortion and unwanted cabinet resonance. Manufactured using premium rubber and durable ABS materials, these passive radiators provide excellent flexibility, durability, and long service life. They are ideal for upgrading Bluetooth speakers, portable speakers, multimedia speakers, subwoofers, soundbars, and custom DIY audio projects. Whether you're repairing an existing speaker or building a custom enclosure, these passive bass diaphragms help deliver powerful low-frequency performance while maintaining compact enclosure sizes. ⭐ Features Premium quality rubber passive radiator Available in Oval, Square & Round shapes Produces deep and powerful bass response No power supply or wiring required Improves low-frequency performance Reduces speaker distortion Durable rubber suspension Lightweight and compact design Easy to install Ideal for DIY speaker upgrades and repairs 📋 Technical Specifications Product Type: Passive Radiator Bass Diaphragm Material: Rubber + ABS Plastic+Metal Shape: Oval / Square / Round (Depending on Selected Variant) Available Sizes: Multiple Sizes (2040 to 6090 Series) Operation: Passive (No Voice Coil or Magnet) Power Requirement: None Installation Type: Speaker Cabinet Mount Application: Low Frequency Bass Enhancement Color: Black 🔧 Applications Suitable for: Bluetooth Speakers Portable Speakers DIY Speaker Projects Multimedia Speakers Home Audio Systems Bookshelf Speakers Soundbars Subwoofers Wireless Speakers Audio System Repairs Custom Speaker Cabinets DIY Audio Enclosures 📦 Package Includes 1 × Passive Radiator Bass Diaphragm (Size & Shape as Selected) ⚠️ Note This is a passive radiator only and does not contain a voice coil, magnet, or electrical terminals. Product images are for reference only. The actual product may vary slightly in appearance depending on the selected size, shape, or manufacturing batch.
ZK-MT21 bluetooth 5.0 Subwoofer Amplifier Board 50WX2+100W 2.1 Channel Power Audio Stereo Amplifier Tone Board Bass AMP AUX
[Amplifier Board] ZK-MT21 2.1 Channel Bluetooth 5.0 Audio Amplifier Module – 50W × 2 + 100W Subwoofer The ZK-MT21 2.1 Channel Bluetooth Audio Amplifier Module is a compact high-power stereo amplifier board designed for DIY Bluetooth speaker and home audio projects. It supports Bluetooth 5.0 and AUX audio input and provides dedicated left, right and subwoofer channels with adjustable volume, bass, treble, subwoofer volume and subwoofer frequency controls. With a suitable DC power supply and properly matched speakers, the module can deliver up to 50W + 50W for the left/right channels and up to 100W for the subwoofer channel. The board includes protection against reverse connection, overheating, overcurrent and short circuit. ⭐ Key Features Model: ZK-MT21 2.1 channel stereo audio amplifier Bluetooth 5.0 wireless audio input Bluetooth transmission distance up to approximately 15 meters under suitable conditions AUX wired audio input Left + Right + Subwoofer output Output up to 50W × 2 + 100W subwoofer Supports 4Ω–8Ω speakers Adjustable main volume Adjustable bass and treble for left/right channels Adjustable subwoofer volume Adjustable subwoofer frequency Subwoofer frequency adjustment range 20Hz–200Hz Reverse-polarity protection Overheat protection Overcurrent protection Short-circuit protection Compact amplifier board design Suitable for DIY Bluetooth speaker projects 📋 Technical Specifications Product Name: 2.1 Channel Audio Amplifier Module Model: ZK-MT21 Bluetooth Version: 5.0 Bluetooth Range: Approximately 15m Bluetooth Shielding: No shielding Audio Input: AUX + Bluetooth Channel: 2.1 Input Sensitivity: 500mV Amplifier Chip Solution: Domestic power amplifier chip Power Supply: DC 12–24V Recommended Supply Current: 5A or above Left Channel Output: <50W Right Channel Output: <50W Subwoofer Output: <100W Total Configuration: 50W × 2 + 100W Compatible Speaker Impedance: 4–8Ω Recommended Speaker Power: 20–100W Subwoofer Frequency Adjustment: 20Hz–200Hz Product Dimensions: 93 × 90 × 22mm Package Weight: Approximately 185g Protection: Reverse connection, overheat, overcurrent and short circuit ⚠️ Power Supply Warning:Do not connect this module directly to a 24V battery pack. Use a suitable regulated DC power supply as specified for the module. 🎛️ Control Functions MAIN-VOLUME: Controls the overall volume of the left, right and subwoofer channels. R&L CHANNEL-BASS: Adjusts bass level for the left and right channels. R&L CHANNEL-TREBLE: Adjusts treble level for the left and right channels. SUBWOOFER-VOLUME: Controls the subwoofer volume. SUBWOOFER-FREQ: Adjusts the subwoofer cutoff frequency from approximately 20Hz to 200Hz. 🔊 Speaker Selection Left and right channels can be connected to 4Ω–8Ω full-range or mid/high-frequency speakers. Recommended speaker power is 20W–100W. The subwoofer output should be connected to a suitable subwoofer speaker, not a regular full-range speaker. The subwoofer should have suitable low-frequency performance, with the source information recommending a frequency capability of at least 50Hz. Speaker impedance and power should be matched correctly with the amplifier. 🔌 Power Supply Selection The power supply is important for achieving proper amplifier performance and sound quality. A power supply with excessive ripple may increase background noise. Recommended supply: 18V / 19V / 24V with current above 5A Lower-voltage or lower-current supplies can be used, but available output power will be reduced. Insufficient supply current can cause voltage drop, abnormal operation or poor sound quality. If the amplifier is operated near maximum volume, an inadequate power supply may result in distortion. The power supply should have sufficient capacity for the actual amplifier load. Higher supply voltage can provide greater available output power within the module's specified operating range. 📱 Bluetooth & AUX Input The ZK-MT21 provides two audio input methods: Bluetooth Bluetooth 5.0 wireless audio input Bluetooth is the preferred input mode according to the supplied product information. Bluetooth supports automatic reconnection. Once Bluetooth is successfully connected, the module operates in Bluetooth mode. AUX Connect an external audio source through the AUX input. When using AUX, ensure the Bluetooth connection has been disconnected if necessary. 🔧 Applications DIY Bluetooth speakers 2.1 channel speaker systems Home audio projects Portable audio systems Subwoofer amplifier projects Custom speaker cabinets Desktop speaker systems Multimedia speaker systems Electronics and audio DIY projects Replacement/custom amplifier systems 🛠️ Installation & Usage Connect a suitable DC 12–24V power supply to the amplifier module. Connect the left and right speakers to their respective output terminals. Connect a suitable subwoofer to the subwoofer output. Ensure the speaker impedance is within the supported 4–8Ω range. Connect the audio source through Bluetooth or AUX. Adjust the main volume, bass, treble, subwoofer volume and frequency according to your requirements. Start with a low volume and gradually increase it. Ensure adequate ventilation and heat dissipation during high-power operation. ⚠️ Important Precautions Do not connect directly to a 24V battery pack. Use a suitable regulated DC power supply. Do not reverse the power supply polarity. Do not short-circuit the speaker outputs. Do not exceed the recommended speaker power and impedance. Ensure the power supply can provide sufficient current. Insufficient power may cause distortion or abnormal operation. Excessive load can cause the amplifier to heat up and activate thermal protection. Provide adequate ventilation during high-power operation. If distortion occurs at high volume, reduce the volume or use a more suitable power supply. The amplifier's actual output depends on the power supply, speaker impedance, audio input and overall system configuration. 📦 Package Includes 1 × ZK-MT21 Bluetooth 5.0 2.1 Channel Audio Amplifier Module
Passive Diaphragm Radiator Speaker Accessories Showcase Speaker Repair Parts
[Passive Radiator] Product Description: Model: 88 48 Low Frequency Vibration Plate Type: Sound film, diaphragm Material: Rubber Size: 88*48mm Net weight: 35 grams The bass radiator is also called a passive speaker. It is used to replace the inverted tube. The subwoofer made with the radiator has the following advantages compared with the traditional inverted subwoofer. The low frequency diving depth is equal to the back type, but the speed is the same. In this sense, it is faster than the inverted type, using the advantage of a certain closed box, and at the same time completely eliminating the disadvantage of the inverted structure-that is, the wind noise brought by the inverted nozzle. Package Includes: 1 x Passive Diaphragm Radiator Speaker Accessories Showcase Speaker Repair Parts
Rubber Passive Radiator Bass Vibration Plates
[Passive Radiator] The Oval Shape Passive Radiator Bass Diaphragm Rubber Speaker Plate is designed to enhance the low-frequency bass response of speaker systems without requiring additional power. Made from high-quality flexible rubber, this passive radiator works by using the air pressure generated inside the speaker enclosure to produce deep and powerful bass vibrations. Passive radiators act as an alternative to traditional bass reflex ports. Instead of allowing air to escape through a port, the radiator diaphragm vibrates in response to internal air pressure from the active driver, resulting in stronger bass performance, reduced distortion, and improved overall sound quality. These DIY speaker passive radiators are ideal for portable speakers, Bluetooth speakers, subwoofers, home audio systems, and custom speaker enclosures. Their lightweight yet durable construction ensures long-lasting operation and easy installation in a wide variety of audio projects. Available in sizes 4080, these passive radiators allow builders and audio enthusiasts to choose the right size for their speaker design and enclosure. Perfect for DIY speaker upgrades, custom audio builds, and professional speaker system enhancements, this rubber bass vibration plate delivers powerful bass performance without increasing power consumption. ⭐ Key Features Durable Rubber Construction for long-lasting use Enhances Bass Performance and low-frequency response Passive Operation – No Power Required Improves Sound Clarity and reduces distortion Lightweight and Compact Design Available in Sizes 4080 Ideal for DIY speaker projects and audio upgrades Easy to integrate into speaker enclosures 🔧 Technical Specifications Product Type: Passive Radiator / Bass Diaphragm Plate Shape: Oval Material: High-quality Rubber Function: Passive Bass Radiator Operation: Air-pressure driven vibration Available Sizes: 4080variants Installation Type: Speaker enclosure mounting Application: Audio speakers & subwoofer systems 🎯 Applications DIY speaker projects Portable Bluetooth speakers Home theater systems Subwoofer speaker boxes Custom speaker cabinets Audio system upgrades 📦 Package Includes 1 × Oval Shape Passive Radiator Bass Diaphragm Plate
Out of stockTPA3116D2 50Wx2+100W Original IC 2.1 Channel Digital Subwoofer Amplifier Board 12V-24V
[Amplifier Board] This is TPA3116D2 IC 50Wx2+100W 2.1 Channel Amplifier Board 12V-24V. DC12-24V TPA3116D2 2.1 Channel Digital Subwoofer Power Amplifier Board adopts two high-quality TPA3116D2 digital amplifier chips. Sound quality is very good, high efficiency and amplifying power. 50W x 2+100W 2.1 channels (left/right channel and subwoofer channel), high efficiency and low-heat. Users can adjust the volume by themselves easily. It is powered by DC 12-24V, wide input voltage. You can check our others amplifier boards here. Features: Adopts two high-quality TPA3116D2 digital amplifier chips. Good sound quality, high efficient device and power amplifying feature. 50W x 2+100W 2.1 channels(left/right channel and subwoofer channel), high efficiency and low-heat. Powered by DC 12-24V, wide input voltage. User can adjust the volume by themselves easily. Applicable speaker impedance: 4-8 ohm. Just connect the power supply and loudspeaker box, enjoy pure digital music!. Specification Supply Voltage DC 12-24V Main Chip TPA3116 x 2 Channel Type 3 Channels(Left Channel, Right Channel, Subwoofer) Output Power 50W x 2 + 100W x 1 Subwoofer Output Match 4-8 ohm Audio Output Terminals Frequency Response Range 14-100KHz SNR 100dB Switching Frequency 1.2MHz PCB Board Size (LxWxH) mm 100 x 70 x 30 Weight 113g Shipping Weight 0.13 kg Shipping Dimensions 14 × 10 × 3 cm Package includes: 1 x TPA3116D2 50Wx2+100W Original IC 2.1 Channel Digital Subwoofer Amplifier Board 12V-24V
Wuzhi Audio ZK-MT21 Bluetooth 5.0 Subwoofer Amplifier Board 50WX2+100W 2.1 Channel Power Audio Stereo Amplifier Tone Board Bass AMP AUX
[Amplifier Board] Tip: Only when the audio input is sufficient and the power supply voltage/current is sufficient, there will be sufficient output power. The higher the power supply voltage, the greater the output power, and the smaller the speaker impedance, the greater the output power. Please make sure that the power of the adapter power supply is greater than the actual working power of the amplifier! You can check our others amplifier boards here. FAQ: 1. How to choose a power supply? The power supply with the board is very important. The ripple of the selected power supply must be small. A power supply with a large ripple will cause the bottom noise of the power amplifier board to become larger and there will be current noise. The higher the voltage, the greater the current, and the more adequate the output power. The power supply is 12V1A and can be equipped with 3-4inch speakers. If it is above 19V 5A, there is no problem with 8-10 inches, and the power supply must be highly regarded. If the voltage is too low, the amplified sound will easily cause sound distortion. If the current is too low, the speaker will pull down the voltage, which will result in abnormal operation or poor sound quality. It is recommended to use a power supply of 18V19V24V with a current above 5A. If you only have 9V12V or 1A 2A power supply, it can be used but the power is low. When the volume is selected close to the maximum, it may be distorted and affect the sound quality. 2. How to choose a speaker? Regarding speaker types: commonly used speakers are generally 4-8 ohms, which can be used. The left and right channel speakers need to be connected to full-range speakers or mid- to high-frequency speakers, and the power is between 20W-100W. The subwoofer speaker cannot be connected to an ordinary speaker, and a speaker with a subwoofer speaker must be connected with a power between 20-100. The dive frequency of the subwoofer speaker must be at least 50 Hz. If your speaker has a low power, such as between 20W-50W, it can be used. You need a lower power supply voltage to prevent the speaker from burning after amplifying the sound. For example, choose a power supply below 15V. If you are a 50W-100W speaker, don't worry about the problem of speaker burnout. You can choose a 12-24V power supply. The higher the selected voltage, the greater the sound or power that can be output. The speaker power should not exceed 100W, otherwise it will affect the sound quality. 3. Introduction to audio input mode This audio power amplifier module has two audio input methods: one is Bluetooth input, the other is AUX input, Bluetooth mode is preferred. Bluetooth can be connected in any mode. As long as the Bluetooth connection is successful, it is in Bluetooth mode, and the Bluetooth mode supports automatic connection back. When Bluetooth is not connected, AUX plug-in is in AUX mode. It should be note that when using AUX mode, you need to confirm that the Bluetooth connection of this module has been disconnected. 4. How to adjust the main volume? The MAIN—VOLUME knob adjusts the main volume. Right-handed main volume increases, left-handed main volume decreases. The main volume affects the volume of the left and right channels and the subwoofer. 5. How to adjust the left and right channel high and low sounds? The R&L CHANNEL—BASS knob controls the bass, right-turning bass enhancement, left-turning bass attenuation. When the knob is in the rightmost position, the bass is neither enhanced nor attenuated. The R&L CHANNEL—TREBLE knob controls the treble, the right-handed treble is enhanced, and the left-handed treble is attenuated. When the knob is in the middle position, the high pitch is neither enhanced nor attenuated. Note when adjusting the treble and bass: when the treble or bass is adjusted to the maximum by turning right, if the sound is distorted, the gain of the treble or bass adjustment is too large. You need to turn the treble or bass knob to the left to lower the gain or turn the right Turn the MAIN-VOLUME knob to the left to reduce the total volume. 6. How to adjust the subwoofer? SUBWOOFER—VOLUME knob is used to control the volume of the subwoofer. Right-handed volume increases, and left-handed volume decreases. The SUBWOOFER—FREQ knob controls the cutoff frequency of the subwoofer. The right-hand frequency increases, and the left-hand frequency decreases. The frequency adjustment range is 20HZ-200HZ. 7. The voice is small and okay. When the voice becomes louder, the voice becomes muddy? The sound is distorted, please turn down the total volume or change to a higher voltage adapter power supply. 8. The sound is small, but when the sound becomes louder, the sound freezes? If the input power is insufficient, the power supply itself is protected against intermittent power failure. Please replace it with a higher-power power supply; or if the power is too large, the power amplifier board will generate serious heat and thermal protection has occurred. Reduce power usage or enhance heat dissipation. 9. What factors are related to the sound quality? The sound quality is not only related to the power amplifier module, but also related to the power supply, sound source, and the entire audio system. Basically, every aspect of the audio system will affect the sound quality, among which the main links are the audio transmission line, the audio power supply, the tone circuit, the power amplifier circuit, the speakers and the surrounding environment. The sound quality is the best only when the sound source, power supply, amplifier module and speakers are matched. Feature: Product Name: 2.1 channel audio amplifier module Product Model: ZK-MT21 Bluetooth Version: 5.0 (no shielding, 15 meters) Input Sensitivity: 500mV Audio Input: AUX + Bluetooth Channel: 2.1 Chip Solution: Domestic power amplifier chip Power Range: DC 12-20 V / 5A above (Do not connect to 24V battery pack) Adapter Speaker: 20-100 W, 4-8 Ω Output Power: Left and right channels <50W, Subwoofer <100W Protection Mechanism: Anti reverse connection. Overheat. Overcurrent. Short circuit Product Dimensions: 93mm*90mm*22mm Package Weight : about 185g (packaging) Package Includes: 1 x ZK-MT21 bluetooth 5.0 Subwoofer Amplifier Board 50WX2+100W 2.1 Channel Power Audio Stereo Amplifier Tone Board Bass AMP AUX
XH-M139 50Wx2+100W 2.1 Channel Digital Subwoofer Amplifier Board 12V-24V
[Amplifier Board] DC12-24V 2.1 Channel Digital Subwoofer Power Amplifier Board adopts two high-quality digital amplifier chips. Sound quality is very good, high efficiency and amplifying power. 50W x 2+100W 2.1 channels (left/right channel and subwoofer channel), high efficiency and low-heat. Users can adjust the volume by themselves easily. It is powered by DC 12-24V, wide input voltage. Features: Adopts two high-quality digital amplifier chips. Good sound quality, high efficient device and power amplifying feature. 50W x 2+100W 2.1 channels(left/right channel and subwoofer channel), high efficiency and low-heat. Powered by DC 12-24V, wide input voltage. User can adjust the volume by themselves easily. Applicable speaker impedance: 4-8 ohm. Just connect the power supply and loudspeaker box, enjoy pure digital music!. Specification Supply Voltage DC 12-24V Main Chip CS3835E0x 2 Channel Type 3 Channels(Left Channel, Right Channel, Subwoofer) Output Power 50W x 2 + 100W x 1 Subwoofer Output Match 4-8 ohm Audio Output Terminals Frequency Response Range 14-100KHz SNR 100dB Switching Frequency 1.2MHz PCB Board Size (LxWxH) mm 100 x 70 x 30 Weight 113g Shipping Weight 0.13 kg Shipping Dimensions 14 × 10 × 3 cm Package includes: 1 x DC12-24V 2.1 Channel Digital Subwoofer Power Amplifier Board
NE5532 2.1 Channel Tone Preamplifier Board Audio Equalizer Subwoofer Preamp Tone Control Bass Pre Amplifier DC10-24V
[Amplifier Board] Product Introduction The product innovation uses a single power supply, which can share power with the power amplifier board. It is very convenient to use NE5532 as the operational amplifier. The operational amplifier IC base is welded to facilitate the replacement of the operational amplifier, and improve the playability. All CBB capacitors are Philips capacitors, and Potentiometer are high-quality platform produced sealed Potentiometer. You can check our others amplifier boards here. Product parameters Product name: 2.1 channel front stage board Frequency adjustment range: 22Hz-300Hz Power supply voltage: DC10-24V Operational amplifier model: NE5532 Board size: 82x30mm Number of channels: single/dual channel input possible Board thickness: 1.6mm Audio input: onboard terminal Centre-to-centre distance of Potentiometer: 3cm * 3cm
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Subwoofer 4 Ohm 3watt [ 2inch/50mm ] Speaker
[Speakers] Features – Product Name : 3 Watt 4 ohm 2-inch Acoustic Speaker Power: 3-5W Impedance: 3-4 Ohm Type: External Magnetic Size : 2inch/50mm (approx) Colour: Black, Bronze Tone Material: Aluminum, Metal, Plastic, and Magnet. Weight: 70g External magnet depends on stock This is non returnable product Note: This is a low-cost non-branded product. We don't guarantee nice output and product finishing. We dispatch randomly as per color and brand availability.
Out of stockHome Theater Board: 2.1 Home Theatre Circuit Board Three 2030 Transistor
[Amplifier Board] Description This is a 2.1 Home Theater Amplifier Board with a capacity of 100W Audio output. Use this 2.1 board for replacement or build your own home theatre. This can be used in 2 channel sound system with one subwoofer to get full bass boost mode. Note: This kit is not for the electronics hobbyist. Proper knowledge about the subject is required to understand and make the complete project. We do not hold any responsibility for any issues or help either due to negligence, ignorance or lack of proper knowledge about the subject. Specification / Feature Stereo Digital Audio Output With TDA2030 circuit, gives high-quality sound Input voltage 12-0-12 V Input current 1.5 to 3 amp Output Power 100 Watt Connection: Connect 2 speakers and 1 subwoofer Package Includes: 1 x 2.1 Home Theater Circuit Board Three 2030 Transistor * Image is only for representations.