ZK-HT21 TDA7498E Bluetooth Amplifier Board 160W×2+220W Subwoofer 2.1 Channel Audio Receiver Power Amplifier Module with Treble and Bass Control for DIY Speakers

This amp provides a lot of bang for your buck! You havento do a little minor assembly, which I wasn't expecting, but it's simple and a screw driver is provided. I'm powering it with a 20v DeWalt tool battery to drive no less than seven speakers in a custom enclosure - 1ea 10" Klipsch sub, 2ea 10" Ashdown mid/woofers and 2 pairs of 2.5" Klipsch high frequency drivers with 1" poly dome tweeters. And it effing rocks! After pairing it in my phone, the Bluetooth connects quickly every time I power the rig up. The fidelity is excellent. Crisp highs, detailed mids and plenty of power to drive the sub, especially with the sun frequency set higher. At lower settings where it rolls off more mid-lows its power does drop off, but, with a tiny plate amp like this that's to be expected. I'm honestly blown away with how much bass thin amp can produce. With more use I will have more info on longevity (and battery life, but,that's not related to this review). Well worth the money for what you get!!

I own a lot of chip amps and this is the highest power one that I've picked up so far. If you've used any other TDA chip boards then you know what you're getting into. Sound quality is pretty exceptional for what you're paying, and the power output when properly spec'd is outstanding. I am using this one for a homegrown portable column array + subwoofer event speaker setup. I have hooked this up to a regulated bench supply set at 36v and run it with speakers wired to take the full rated WPC power at 4 ohm loads. It goes to ridiculous volume levels with no audible distortion and draws far fewer amps than the spec sheets and PSU requirements would suggest. I think I saw a peak of less than 4 amps of draw, whereas I was expecting twice that or more. The unit runs cool, especially with the fan running. The fan is very quiet, too. You won't hear it at all in a public venue. Heck, you can barely hear it in a quiet room. I am not sure if the variable crossover is just a low pass for the sub, or if it is a high pass for the stereo pair as well, but I make passive crossovers for my speakers so I haven't worried about it nor tested the output with an oscilloscope either. Anyway, this is a cheap, clean and powerful little amplifier if you load and power it properly. I would highly recommend it.

This is an incredible amp for the price. Bluetooth connectivity is great! Love the separate subwoofer channel as well. Great for at home audio projects! Paired mine with a 24V laptop power supply and works great!

I'm seriously impressed with the sound quality this amp produces. I purchased the zt21 about a month prior to this one. But the zt21 kept popping while playing music. Thought it was capacitor so swapped it out but still the same issue. Then I noticed if I blew on the heat sink when it started to pop, it would stop. Placing a fan on top solved the problem. So that's why I chose the HT21, because of the built in fan, but was surprised at how much cleaner it sounds. And the knobs to control the Frequency, Bass, Treble, and Volume are much more accurate & smoother than the zt21. Bluetooth sound quality is significantly better as well. I use a 24V 5A LED Driver power supply for good clean power, but I also use ~ 30V high amp 18650 lithium battery packs I make, when I want my system to be portable. Overall, this is a much better amp than the zt21, it may be more expensive, but well worth the price. Just remember to use a good quality power supply or battery pack for a nice clean sound. This one can take up to 36V/ ~10-12 Amps I believe.

I have an old farm truck that didn’t have a stereo so I bought this to put in it. I run 4 speakers (two speakers per channel) wired appropriately and a 10” subwoofer. It’s running on 20v through a 12v-20v step up. Super loud. Bass from the subwoofer is pretty powerful for how small this thing is. Sound quality is clear and overall pretty decent. The reason for 4 stars is because the “frequency” knob that is used to adjust the pitch of the subwoofer doesn’t seem to do anything. I have used other amplifiers like this one before and that knob does create a minor but noticeable change in the sound of the subwoofer. Not really that important though and works great otherwise.

I’m impressed with this little amp board kit. The only gripe I’d have is the little fan barely making noise but that’s nit picking because it’s whisper quiet. Back to positive feedback. 1: Driving retro JBL speakers from the 80s with 5 1/2 inch drivers. 150w 8ohm. Sound perfect. 2: Bluetooth links with Apple TV4k. Flawlessly 3: Driving 2 40w exciters with 1 50w shaker from sub channel. (Have to turn down gain and volume still). 4: Links to iPhone flawlessly. 5: Sub channel has separate volume and gain. 6: bass and treble have separate gain. 7: Volume control. 8: Quality heat sink. 9: Plenty of power to drive power hungry 80s speakers. 10: Tiny footprint with plenty of undistorted sound coming from speakers. 11: Quality capacitor array. I’m honestly impressed. My recliner rock and rolls and I’m only using 16vdc @4Ah and I could add 1 more bass shaker easily. If I turned up the gain and volume on the sub channel I’d blow up chair.

For an amplifier, it's a great price point and has great output power. Fan is a little loud, but I unplugged the fan and it stays cool when not driven hard (running at 19V). BT audio processing time is a bit frustrating. Unlike most of my other bluetooth audio devices, there is a delay. While it's not significant, it's enough to drive you crazy when watching a video of someone speaking (slow speaking is not as problematic). For music however, or any other source that does not require audio and video to be perfectly synced, it's fine. Aux input does not have this delay, only bluetooth. UPDATE: Changed from 4 stars to 3, due to what seems to be an input threshold required to output sound via bluetooth (kind of like a a subwoofer amp that turns on/off automatically when it detects input). Listening to some classical music, I noticed it cutting out between notes. Tested on two different devices (phone and laptop) the same piece sounds perfect via aux input, but the quietest parts are missing when playing via bluetooth. As a note fades toward silence, it suddenly cuts the output completely, and restores output just AFTER the next note starts. This is a MAJOR flaw that means I'll be using a separate bluetooth adapter for this amp, rendering all onboard bluetooth functions useless.

Bought 2 , great amp . Runs my highs and my subs .

Best product

Tiene. Un buen sonido. De calidad. En un dispositivo pequeño. Ay. Un gran. Equipo de audio execelente

El sonido es bastante bueno.... Para un amplificador tan pequeño. Bastante resistente en cuanto el voltaje. Muy bueno por calidad y precio... Lo recomiendo mucho si empiezan en el mundo del audio

Best product 👍👍👍👍👍👍👍👍👍

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