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50W+50W+100W 2.1 Channel Subwoofer Amplifier Board with Treble and Bass Control, Dual TPA3116 Chip, DC 12-24V, Bluetooth and AUX Inputs, DIY Wireless Speakers AMP Board, Password Free (ZK-TB21)

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Availability: In Stock.
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Arrives Thursday, May 23
Order within 8 hours and 43 minutes
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Model: ZK-TB21


Features

  • TPA3116D2 HIFI Chip Solution: Stereo Dual-channel Output to Ensure Continuous Serial High-power Operation, THD 0.1%. Wide Voltage Input DC: 12-24V;
  • Treble & Bass Control: If You Are Tired of The Inherent High& Low Bass, Why Not Try The High & Low Control Knob! This Will Make You Feel Like Being In A Movie Theater.;
  • Bluetooth and AUX Function: Bluetooth 5.0 version, Transmission Distance Is Farther. The Transmission Distance Can Reach 49 Feet In An Open Environment. If your Play Device Does Not Have Bluetooth, You Can Also Input Audio Signals Through The 3.5MM Headphone Plug.;
  • Safety Protection: This Amp Board Has Overheat Protection, Reverse protection, Circuit Protection, Over-voltage and Under-voltage Protection;
  • 7 * 24 Hours After-sales Service: Paying Attention To Customer Experience And Satisfying Customers Is Our Service Tenet. If You Have Any Questions About The Product, or The Product Has Quality Problems, Please Contact Us At Any Time, We Will Give You A 100% Satisfactory Answer.

Item Dimensions LxWxH: 47.24 x 39.37 x 8.66 inches


Voltage: 24 Volts


Manufacturer: DAMGOO


Mounting Type: Surface Mount


Brand: DAMGOO


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 47.24 x 39.37 x 8.66 inches; 6.88 ounces


Item model number ‏ : ‎ ZK-TB21


Date First Available ‏ : ‎ May 7, 2020


Manufacturer ‏ : ‎ DAMGOO


Country of Origin ‏ : ‎ China


Best Sellers Rank: #16,007 in Electronics (See Top 100 in Electronics) #42 in Audio Component Amplifiers


#42 in Audio Component Amplifiers:


Customer Reviews: 4.4 out of 5 stars 971


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, May 23

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • In......credible
Model: ZK-TB21
I have not taken any pics yet so I will add them when it’s all ready, but I will say that I’m blown away with this little beast. I have been a car audio competitor for around 20 years now and have 2 world titles. I purchased the zx-100zl first to test the waters and still have it as the outside patio stereo and theater system. So I did not hesitate when my finger clicked on the order button for this 3 channel with separate sub unit with the treble, bass, sub volume, cross over control,and main volume knobs, which are very smooth and adjust flawlessly with no static or interference noises rolling out at all. The built in crossover is a little disappointing and is more like a cut frequency and wattage knob. I have hooked up a hand full of subs and pro woofers to see if box design would help or sub specs might be a factor but they all have the same sweet spot and going below that just kills the output, but the sweet spot is right at the spot that it needs to be anyway with every genre I went through, for me anyway. If possible try to get the unit as close to 24v as you can or at least 20v if you want to be able to utilize the units full potential. I am using a small digital voltage regulator or buck unit inline with the 19v laptop charger. That way I can just turn the adjustment knob up or down to go to 24v or down to 9v if I want to for some reason put some small 5w speakers on it, I won’t.. the sound clarity is flawless through the whole scale. Tweet response is on point. Mids and vocals are clear and powerful. If you keep the sub crossover above half way which seems to be around 100hz, you won’t loose any significant power. Over 100hz out of sub starts distorting the lowend vocals anyway so it works fine. I ended up putting a passive sub crossover inline out of the unit anyways just cause I already have some and it seems to really open up the wattage flow that the units crossover was smothering. At the moment I have 4 Yamaha 3 way 100w bookshelf speakers on the 2x50w full range channels and 2 6.5” subwoofers in a down fire custom built ported sub box tuned to 45hz on the 100w sub channel. I have it bluetoothed to my theater in my home office, aka work space, gaming system and second theater room. I can go from a virtual power point webinar to streaming John wick 3 on the 4K, to madden 21 on the xbox one or asphalt 9 on the gaming pc, and this little marvel is crisp, clean, clear, and will have the neighbors yelling at me with no problems. I highly recommend this bad boy even if you don’t need it. You will find a use for it. You will make use for it anyway. It’s that good.. also I would like to give 5 stars to the damgoo team for all the quick responses and customer first mentality that they seem to have perfected and have done nothing less then been amazing and don’t make you feel like just a customer but a personal friend from the first interaction. If everyone conducted business the way they do, the world would be a little nicer to itself.. sorry for the long winded review but how else could I have explained it. Awesome... ... show more
Reviewed in the United States on February 8, 2021 by Jeremy

  • Overly impressed, a lot of bang for your buck if you understand speakers & set-up.
Model: ZK-TB21
I have been looking at these inexpensive little amps for a few years and never really had a use for one, as I have a pile of older amps around the house for my systems. I have been upgrading my home office and decided it was time to bring some solid music playing into the office, as I do my best work with LOUD music ;-). had a pair of Polk bookshelf speakers that had been sitting in their original box for a few years from when I picked them up on sale from Frys. wanted a small amp to drive these off my PC, Alexa, and TV, and I liked the idea of how small this amp was and could mount it under my desk. had concerns about such a small amp pushing 8-ohm speakers as most folks were using it with 4-ohm set-ups. If I got I could return it it and did not like the sound/power, I could e you do need to do some assembly, and I recommend some felt feet if you plan to put this on a surface. Assembly was easy, and I quickly wired up the Polks. At first, they sounded like crap, but then I started to play with the tone and slowly dialed them in. The Sound got better as time went on. Like most amps/speakers, I find they need a little time to warm up, and the sound gets richer. With just the polls, I got pretty good sound and loud enough to annoy my wife. But, the amp would distort at the highest output. The Polks do not have a very low range, so the base was lacking. This is where I made a mistake when choosing this amp. It has a powered output for the sub amp, so you need a passive sub, and most home subs on the market today are powered. I did not want to spend a fortune on a sub, so I looked into making one and came up with a cost of about $50-80, depending on what drivers I chose. Then it occurred to me that a lot of the 'home media' speaker set-ups come with a passive sub, so off I went to eBay. I bought a refurbed SONY passive sub for $30 delivered on eBay. I got it and hooked it up, and immediately, the package was complete. With the sub hooked up, this amp has plenty of power to drive all 3 speakers and get very loud without any distortion. Still dialing it in some more, but it just gets better. If you want a cheap little set-up that you don't need 'high-end' sound, this is the amp for you. I think I will pick up a few more to drive my outdoor speakers this summer because I can hide the amp just about anywhere and very little heat. I did have to buy a power cord for a few bucks, but you can use an old laptop cord if you have one. ... show more
Reviewed in the United States on March 24, 2023 by ShopperX ShopperX

  • The amp is very good, bluetooth not so much.
Model: ZK-TB21
This is a fine little amp for a bookshelf system, as long as you make sure that the power supply you pair it with has enough power. I need maybe 15-20 watts per channel, so I used a 12 volt/60W power supply, input sound from a DAC + digital sound source using the 3.5 mm jack, and connected it to a pair of old Polk Monitor 30s, which are 8 ohm speakers. The sound was very good with these bookshelf speakers. No distortion, hum or noise as far as I could tell. It really sounded to my ear as good as my big receiver. I was impressed. But only with the 3.5 mm jack (see below). A couple of caveats, though: - The bluetooth in the amp worked but is very poor sound-wise - everything sounded compressed and flat to my ear. I don't use it. If I play the same music through the 3.5 mm jack using the bluetooth in my digital system + DAC, it sounds 10 times better from the same bluetooth source. So it's clearly the internal bluetooth/DAC that is the problem, not the amp. It would be better if it didn't have the bluetooth at all, it's a nuisance in my opinion, because it stays on all the time, and there is no way to turn it off as far as I can tell. Will a neighbor accidentally pair with it and interrupt my music? Time will tell. - I did hear a small pop powering up the sound source one time. But nothing after that. We'll see how it holds up over time. ... show more
Reviewed in the United States on January 7, 2024 by TC

  • Exceeded my expectations
Model: ZK-TB21
Got this little guy to power a couple 6x9's and a 8 inch subwoofer for out in the garage. With the proper power supply this thing rocks, louder than I had ever expected. It pushes both 6x9's and the subwoofer without a problem. Hands down better than any Bluetooth speaker I've purchased and only 25 bucks. Delivery was fast with product and packaging not damaged. Will be getting the more powerful one next. Would recommend ... show more
Reviewed in the United States on February 29, 2024 by Kristine Bushee

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