ZK-AS21 HT21 HIFI Digital Power Audio Amplifier

Wuzhi Audio Adownload link:

(This version of ais compatible with the operation of new products. Please download and update the abefore using the product.)

http://www.qingdaowuzhi.cn/btapp/Wuzhi_Audio_V1.0.3.apk

Note!

It needs to be aembled by yours, and the material package is given a screwdriver.

The suitable power supply of the product is DC power supply, and AC power supply is not allowed!

The color of the product may be slightly different from the picture due to the differences of light, angle and shooting equipment.

The product size is measured manually. Please allow slight deviation in the measurement data and make sure you don't mind.

ZK-AS21 and ZK-HT21 are two high-power 2.1 channel digital audio power amplifier board modules, treble and ba tone adjustment ， subwoofer adjustment. There are four audio input modes: AUX input, input, USB disk input, USB sound card input, left and right channels + subwoofer output, Dial the wheel on to switch modes and songs, Claic mechanical volume knob, turn the knob to switch thehine on and off, no need to pre and wait to see the indicator light. Long life and low noise fan is used for air cooling and heat diipation.

ZK-AS21 adopts TPA3255 power amplifier , version 5.1, the maximum output power of left and right channels is 220W + the maximum output power of subwoofer is 350W, the voltage gain is 30dB, the adaptive power supply is DC16-38V, ≥ 10A, the left and right channels of speaker are 30-220W, 3-8 Ω, subwoofer is 30-350W, 2-8Ω, and supports Wuzhi Audio APP.

ZK-HT21 adopts TDA7498E scheme, with filter output, HIFI sound quality, version 5.0, maximum output power of left and right channels of 160W, maximum output power of subwoofer of 220W, and adaptive power supply of DC15-36V. The adaptive speaker is 30-200W, 4-8 Ω.

ZK-HT21 is upgraded to support Wuzhi Audio APP, to box function, more lole formats, MP3, WMA, FLAC, APE, WAV (maximum WAV bit rate is 3072kbps).

Supports USB flash drives with larger capacity, 64G or le.

Model： ZK-AS21

ZK-AS21 product parameters

Brand: Wuzhi Audio

Product Name: 2.1channel digital power amplifier board module

Product Model: ZK-AS21

Amplifier : TPA3255

Channels: 2.1 channel (left channel + right channel + subwoofer)

Audio Input: AUX ++U disk + USB sound card

Version: 5.1

Switching Mode: Mechanical switch(without long pre and wait)

Adaptive Power supply: DC16~38 V ,≥10A

Adapter Speaker: L&R channels 30-220W，3-8Ω, Subwoofer 30-350W，2-8Ω

Output Power: R&L channel≤220W, subwoofer≤350W

Protection Mechanism: Protection against reverse connection, undervoltage, overheating,overcurrent and short circuit (automatic recovery without restart)

Voltage Gain: 30dB

Product Size: 141*131*27mm

Product Weight: about 346g

Package Weight: about 408g

Tip: when the audio signal input is large enough and the power supply voltage / current is large enough, there will be enough output power!

The higher the power supply voltage, the greater the output power, the smaller the speaker impedance, and the greater the output power!

Please ensure that the power of the adaptive power supply is greater than the actual working power of the power amplifier!

ZK-AS21 dial wheel on to switch songs and modes

① Switch song on and mode on.

You can switch songs without using your mobile phone.

ZK-AS21 product Introduction

There is a clear distinction between the power input terminal and the speaker wiring terminal to prevent the speaker from being connected to the power terminal and burning the speaker.

① Power input (5.5X2.1 DC plug and 2P terminal)

② Subwoofer

③ Left channel

④ Right channel

⑤ USB flash disk/USB sound card input

⑥ AUX input

⑦ Subwoofer frequency (20-200HZ)

⑧ Subwoofer volume

⑨ Left and right channel treble

⑩ Left and right channel ba

⑪ Total volume / switch

⑫ Dial wheel on

ZK-AS21 dial wheel on

Pre the on to switch the song switching mode, which is convenient and fast.

① Dial wheel on

② Pre in from the middle:

Short pre: Pause/Play

Long pre: Switch mode (USB/BT/AUX）

③ Turn the on to the left:

Short pre: Previous song

Long pre: Volume -

④ Turn the dial on to the right:

Short pre: song

Long pre: Volume +

ZK-AS21 the operational amplifier has large gain

One more level of amplification can ensure full output power

① Changing the R and L resistors can the DIY gain

② Six low noise preamplifiers 5532

Improve the sound quality and volume, increase the gain, and the gain parameter is 30dB.

ZK-AS21 detail determines quality

①② The product is designed with two Texas Instruments TPA3255 power amplifier s.

TPA3255 is a high-performance cla D power amplifier. It has cla D efficiency and can bring real high-end sound quality. The device features advanced integrated feedback design and proprietary high-speed gate driver error correction function (PurePath TM HD). This technology can make the device maintain ultra-low distortion in the whole audio frequency band and show high-definition sound quality at the same time.

③ Window tin spraying design

Tin spraying design of wiring window.

Increase output power.

④ Tin spraying design of wiring window

Wiring on the back of bare board, window opening and tin spraying.

Increase output power.

ZK-AS21 installation example of external antenna（Same as ZK-HT21）

① Example of antenna base welding

② Antenna base

③ 2.4G antenna

④ Example of antenna welding

Note: The antenna and antenna base should be purchased by yours.

ZK-AS21 EU safety certification

30dB high gain, effectively ensuring high power output.

The mechanical on turns off without waiting,which is convenient and fast.

Steple tuning, volume adjustment with indication.

ZK-AS21 installation Diagram

① M2*4 screw

② Upper cover board

③ Knob

④ M2*18 copper pillar

⑤ M2*5+4 copper pillar

⑥ M2*4 screw

⑦ Lower cover board

⑧ PCB

⑨ Free screwdriver

Wuzhi Audio ASleeping Music

Lullaby music allows you to return to nature, help you sleep, decompre and heal your body and mind. Wuzhi Audio Ahas the function of regular shutdown.

10 natural sounds are Sound bowl, Stream, Wave, Sea wave, Thunderstorm, Bird song, Cry of insects, Frogs, Bonfire, Guqin, up to 1023 sound combinations.

10 kinds of natural sounds create unique natural sound scenes, create a natural atmosphere, quickly calm your mood and realize deep sleep.

Wuzhi Audio AFunction

Change name:

The name of each product can be changed, and multiple products can be easily identified.

Change paword:

The connection paword can be modified to prevent others from hijacking. This function can be turned off.

Adjust the volume of prompt tone:

The volume of prompt tone can be adjusted to meet different needs of customers.

ON / OFF prompt tone:

The prompt tone can be turned on or off.

ZK-AS21: USB flash disk playlist function

Open the playlist of USB flash disk, select music at will, and support shaking to switch songs.

ZK-HT21: Firmware Update

ASetting Interface

ZK-AS21 setting interface:

ZK-HT21 setting interface:

name modification steps:

[enter a new name] → [click set on] → [system automatic restart] → [cancel pairing of mobile with the original name] → [find a new name and re pair]

paword setting steps:

Method 1:

[turn on paword switch] →Use default paword 1111

Method 2:

[turn on paword switch] → [enter paword] → [click the setting on] → [the system will restart automatically] → [cancel pairing, and you will be prompted to enter paword when connecting again]

Model: ZK-HT21

ZK-HT21 parameters

Brand: Wuzhi Audio

Product Name: 2.1 channel audio amplifier module with tone

Product Model: ZK-HT21

Version: 5.0（no shielding, 15 meters）

Audio Input: AUX + +USB（Dial wheel on toggles songand mode）

Channel: 2.1（Left channel + right channel + subwoofer）

Solution: TDA7498E

Adaptive power supply: DC15~36V （Under voltage protection below 9V, and 12V power supply can also be supported）

Adapter Speaker: 30-200W，4-8Ω

Output Power: Max160W @ R&L channel, Max220W @ subwoofer

Protection Mechanism: Anti reverse connection, undervoltage, overheating, overcurrent, short circuit protection

Product Size: 145*126*28mm

Product weight: net weight 327g, package weight 395g

ZK-HT21 Product Details

① USB disk/USB sound card input (Support lole WMA/FLAC/APE/MP3/WAV/M4A format)

② Low noise front stage operational amplifier

③ Large capacity energy storage capacitor

④ Filter circuit

⑤ Antenna base welding (The antenna and antenna base can be welded)

⑥ PWR work indicator light

⑦ indicator light

⑧ Dial wheel on

⑨ Long life ultra silent fan (Locked rotor, no burning, no noise)

⑩ Upgrade de

ZK-HT21 Product Introduction

① Power input (5.5X2.1DC plug and 2P terminal)

② Subwoofer

③ Left channel

④ Right channel

⑤ Audio input (- AUX)

⑥ USB_IN

⑦ Subwoofer frequency (20-200HZ)

⑧ Subwoofer volume

⑨ Left and right channel treble

⑩ Left and right channel ba

⑪ Total volume / switch

⑫ Dial wheel on

ZK-HT21 dial wheel on

① Dial wheel on

② Pre in from the middle:

Short pre: Pause/Play

Long pre: Switch mode(USB/BT/AUX）

Triple hit: turn on or off

③ Turn the on to the left:

Short pre: Previous song

Long pre: Volume -

④ Turn the dial on to the right:

Short pre: song

Long pre: Volume +

ZK-HT21 Installation Diagram

① Knob

② Upper cover board

③ M2*18 copper pillar

④ M2*4 screw

⑤ Lower cover board

⑥ PCB

⑦ M2*5+4 copper pillar

ZK-HT21 Box matching function

interconnection

Two power amplifiers are used together

Introduction to box matching function and operation:

1. Turn on two power amplifiers of the same model.

2. Select a power amplifier at will, and pre the total volume knob with key function inwards three times. At this time, the red indicator flashes, and the other power amplifier is automatically paired with it as a stereo combination. (if the pairing is not succeful within 15 seconds, the pairing mode will be canceled automatically. You can try again by preing the key three times.)

3. If the pairing is succeful, the selected one will be aigned to the left channel, and the red indicator will always be on. The other one is the right channel, and the red indicator will flash slowly.

4. The time you start thehine, you will automatically find the right box. If you want to cancel the box matching mode, you only need to select a power amplifier and pre the on three times.

About shipping
Shipping and Packaging All itwill be double checked and well packed before sending.Itwill be dispatched within 2 business days after buyers pay for the order. It usually takes about 14 to 18 working days for delivering the package to the destination(for e areas,it may take a little longer). 

Special Announcement:
Please fill in the correct and detailed consignee, address and phone number in the order. For fast and correct delivery.If you do not receive order within 30 working days,please feel free to contact Customer Service before leaving Negative and Neutral Feedback, we will do our best to help you resolve the problem.TaxNo, you will only pay what is quoted as total cost at checkout, no more. You are not expected to pay any additional duties ores. If you are asked by Customs or our logistic partner to pay duties, please contact our Customer Service .

Your 100% satisfaction is very important to us
If the product is not on good condition, You can return this product within 14 working days, please contact customer service center before returning.FeedbackYour satisfaction is our first priorityIf you receive the order and it is in good condition,we would be grateful if you would leave us 5 star Positive Feedback for the transaction.