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ZK-TB21 TPA3116D2 bluetooth 5.0 Subwoofer Amplifier Board 50WX2+100W 2.1 Channel Power Audio Stereo Bass AMP
253
Shipping to: United States |
Express delivery: 7-12 business days |
Standard delivery: 15-25 business days
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Return PolicyFree Gift
Welcome to Roymall, your professional website for purchasing premium department store gifts. We highly value and appreciate your support, and we want to express our gratitude by adding an extra touch of excitement to your purchases. When you shop with us, you not only get to enjoy high-quality products that enhance your lifestyle, but you'll also receive an exclusive free gift with every order you place. Ready to explore our collection and find your perfect gifts? Browse our selection of premium department store items, place your order, and look forward to the excitement of your free gift arriving alongside your purchase.Shipping Policy
We will work hard to deliver items to you after receiving your orders and make sure they arrive safely. Delivery details will be provided in your confirmation email.In most cases, orders are processed within 2 days.Under special circumstances, it will be delayed as follows: When you place an order on Saturday, Sunday or public holidays, it will be delayed for 2 days..Normally, it needs 5-7 working days (Monday to Friday) without being affected by flight delay or other environmental factors..Because our shipping service is worldwide so the delivery times will depend on your location so it may need a few times and please wait patiently if you are in remote districts or countries.1. Return & Exchange Policy
We only accept items purchased from roymall.com. If you purchase from our local distributors or other retailers, you cannot return them on our side. Final sales items or free gifts are not acceptable for a return. To be eligible for a return, your item must be unused and in the same condition that you received it. It must also be in the original packaging.After receiving return instructions from us, please package up your returned items and drop your package at the local post office or another courier.We will process your return or exchange item within 3-5 working days after we receive it. The refund will be processed and credited automatically to your original method of payment.No returns or exchanges can be accepted if the product was custom produced, including custom size, custom color, or custom printed.Need more help, please contact us. service@roymall.com or Whatsapp: +8619359849471
2.Refund Policy
You'll get a full refund or 100% store credit after we receive the returned package and check it. The refund will be processed and credited automatically to your original method of payment. Please note that shipping costs and any duties or fees are not refundable. The extra shipping costs are non-refundable once the package has been shipped. You are responsible for paying these fees and we’re unable to waive or refund them, even if the order is returned back to us.Once we received and confirmed your returned item, we will send you an email to notify you that we have received your returned item. We will also notify you of the approval or rejection of your refund.If you have any problems regarding the refund process, please contact us. service@roymall.com or Whatsapp: +8619359849471Specifications:
Model: ZK-TB21
Material: electronic components
Color: Black
Bluetooth Version: 5.0(no shielding, 10m)
Input sensitivity: 500mV
Audio Input: AUX+Bluetooth
Channel: 2.1
Chip: TPA3116D2(with AM anti-interference function)
Power: DC12-24V/5A
Adapter speaker: 20-100W, 4-8u03a9
Output power: Max.50W(R and L channel), Max.100W(subwoofer)
Protection Mechanism: overvoltage ,undervoltage,overhearing,DC detection,short circuit protection
Size: 118x100x22mm/4.6x3.9x0.8inch
Note:
Transition: 1cm=10mm=0.39inch
Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid.
Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!
Package Included:
1 x ZK-TB21 Amplifier Board
Q&A:
1. How to choose the power supply?
The power supply with the board is very key, the selected power supply ripple must be small, ripple large power supply will lead to power amplifier bottom noise, there is a current sound.The higher the voltage, the higher the current, and the higher the power output. If you only have 12V 1A, you can have 3-4 inch speakers.If you are above 19V 5A, no problem with 8-10 inches, power must be highly valued.If the voltage is too low and the sound is amplified, it will easily cause sound distortion. If the current is too low and the horn cannot be brought up, the voltage will be pulled down, which will lead to abnormal operation or poor sound quality.
It is recommended to use 18V19V24V power supply with current above 5A.If you only have 9V12V or 1A 2A power supply, you can also use it but with low power. When using it, choose the volume close to the maximum, which may cause distortion and affect the sound quality.
2. How to select speakers?
About the speaker type: commonly used speakers are generally 4-8 ohms, can be used.Speakers in left and right channels need to be connected to full frequency or medium and high frequency speakers with power between 20W and 100W.Subwoofer speakers cannot be connected to ordinary speakers. Speakers with subwoofer speakers should be connected, with power between 20-100W.The subwoofer horn must have a dive frequency of at least 50Hz.
If your speaker power is small, such as between 20W-50W can also be used, the power supply voltage needs to be small, to prevent the loudspeaker burnt after loud, such as choose power below 15V.If you are a 50W-100W speaker, you don"t have to worry about burning out the horn. You can choose a 12-24V power supply. The higher the voltage you choose, the more sound or power you can output.Speaker power is not easy to exceed 100W, otherwise it will affect the sound quality.
3. Audio input mode
There are two audio input modes for this audio amplifier module: one is Bluetooth input and the other is AUX input. Bluetooth mode is preferred.Bluetooth can be connected in either mode.As long as the Bluetooth connection is successful, it is bluetooth mode, and bluetooth mode supports automatic back up.AUX insert is AUX mode when Bluetooth is disconnected.It should be note that the bluetooth connection of this module is disconnected when using AUX mode.
4. How to adjust the main volume?
The MAIN - VOLUME knob is used to adjust the MAIN VOLUME.The right main volume goes up and the left main volume goes down.The master volume affects both the left and right channels and the subwoofer volume.
5. How to adjust the height and bass of the left and right channels?
R&L CHANNEL - BASS knob is for BASS, right-handed BASS enhancement, and left-handed BASS attenuation.When the knob is in the right-most position, it does not enhance or attenuate the bass.
The R&L CHANNEL - TREBLE knob is used to control the TREBLE, with right-handed TREBLE enhancement and left-handed TREBLE attenuation.When the knob is in the middle, it does not enhance or attenuate the treble.
Note when adjusting high and low sounds: when the TREBLE or BASS sounds are right-rotated to near maximum, if the sound distortion is distorted, the gain of the TREBLE or BASS sounds is too large. It is necessary to turn the TREBLE or BASS knob to the left to lower the gain or turn the MAIN-VOLUME knob on the right to the left to reduce the total VOLUME.
6. How to adjust the subwoofer?
SUBWOOFER - VOLUME controls the VOLUME of the SUBWOOFER.The right-handed volume goes up and the left-handed volume goes down.
The SUBWOOFER - FREQ knob controls the cutoff frequency of the SUBWOOFER.The right frequency increases and the left frequency decreases.The frequency adjustment range is 20HZ-200Hz.
7.What factors are associated with sound quality?
The quality of sound is not only related to the power amplifier module, but also to the power supply, sound source and the whole sound system.Basically every link of the sound system will affect the sound quality, among which the main link is the audio transmission line, audio power supply, tone circuit, amplifier circuit, speakers and the surrounding environment.The sound quality is best when the sound source, power supply, amplifier module and the speaker are matched.
