I've got the HT21, a MeanWell 36V 10A power supply, 2 large 4-ohm Sony bookshelf speakers with 2 midranges and a horn tweeter in each, and a 10" DVC BOSS subwoofer wired to 2-ohm, and mounted in a Klipsch downfiring box... Lemme tell ya about "BLOW THE ROOF OFF"... This thing will rattle the neighbor's windows, and make your eyeballs vibrate in their sockets... It's got crystal-clear highs, and booming bass that sounds GREAT... I've bought several Aiyimas, and several smaller Wuzhis to install into hardwood cigar boxes to sell... But this one is the best so far... It's truly a BEAST...
there are at least two versions of ZK-AS21 in the market. think you have the older version with TPA3251. they use TPA3255 for the newer ones. you can tell the difference by looking at the lower limit of the supply voltage. 12V is TPA3251 while 16V is TPA3255...
In the video footage, you can definitely see the voltage print 12v, so he got TPA3251 chip which doesn't have the power as in the TPA3255 model which is printed 16V-38V
Just a suggestion... Could you do a side by side of the 2 amps powering the same speakers? I appreciate that we don't get the same sound on RUclips as you do in person, but sometimes you can pick up on the difference in sound relative to each other. Just a thought
I may be able to do something like that soon. I bought some new speakers, a 600w power supply and another HT21 for backup just incase something ever happens. I still have the AS21 aswell, so once I get time I'll try and get a video up
Quick question with regards to the HT21: Does this board have a high pass filter for the tops ? Or is the stereo channel a fullrange signal (including bass) ...this would be worst case! And if there is a highpass: does the cutoff frequency go in sync with the frequency-potentiometer for the sub?
There is only a crossover for the subwoofer, but it doesn't really work lol. The sub channel on all of these mini amps, have vocal bleed. They are crossed around 200hz to begin with, and then the "crossover" filter does whatever from there, but you still have vocals coming through regardless, so it's kinda pointless lol. But if the sub isn't close to you, then it's not a huge deal but something to consider. And the mids/highs only have basic "treble/bass controls, no crossover for them. The treble/bass seem to effect each other also, so kind of have to find a happy medium. That's one of the downfalls of these mini amps, the lack of equalization can make it difficult to obtain a good sound at certain volumes, but overall they do sound good for basic needs. These aren't high end by any means but they have their place, good for basic home audio, garage setup/man cave, portable Bluetooth setups..etc.
Sir, this is my zk-ht21, I have a problem with the output of the R+R- channel on the speaker, there is only a loud bang and the speaker spull is hot. What do you think, sir??
These units aren't built very well, I would just buy a new amp and be done with it. One thing, DO NOT mess with the speaker outputs while the amp is on and playing music. Keep the amp off while wiring speakers up, and then turn it on.
thanks. My newly bought HT21 has a large 60-90w power draw all the time, sending all that power as very low frequency hum to subwoofer so I'm returning it. I'm looking at TPA3255 amps but some reviews share your thoughts on the subwoofer weakness of the AS21
Yeah, ALL of the 3255 amps I've tried have to have the bass turned up quite a bit, unlike the ht21. But they still give plenty of bass once you do that. You might look into the Fosi Audio bt30d PRO, it's a little higher quality build 3255 amp, but lacks a fan, so you may need to disassemble the case and drill some holes, this will keep the amp much much cooler.
@@scarr3ll I found the Fosi and insanely cheap ($62 with PSU) alternative with similar specs. however, I wonder why the recommended power supply for these is 32V - 5 amps. Isn't that underpowered to max the Fosi Audio bt30d PRO?
@zodiacfml yeah, I think they just recommend a smaller power supply because it's cheaper, and most people just want sound right away and aren't worried about getting all the power they can if it's loud enough with the 5a supply.
@@scarr3ll I see, makes sense. I'm looking at this KGUSS PA8 that is the equivalent to the Fosi Audio BT30d pro or an Aiyima. Is the subwoofer/bass gain of the Fosi Audio as good or better than the ZK-HT21?
On witch one subwoofer sounds better? I have xh-a128 amplifier witch uses tda7498e and clearly can hear vocals from subwoofer (amp has no frequency adjustment pot). How these sound with sub. Witch one is better?
The HT21 is better over all. The AS21 requires the Wuzhi App and you have to adjust the eq and main volume of the app itself to adjust the sound of the amp, its weird. Both amps still have vocal bleed. I believe ALL of these mini amps are crossed around 200hz or so. These may benefit being ran through an external eq or something for better control but by that point, you may aswell buy an actual receiver.
I have this KIT both, all ori from wuzhi audio. In App (for AS21), if equalizer set to flat or disable, I will definitely choose HT-21. But if equalizer set to more bass, i prefer AS21, because i think, L-R ch AS21 more and very clarity :D. Just my opinion. by the way, good review,sir.
I've been using a 36v 11amp switching power supply for a long while now and it is what I suggest. Use a voltage withing the amps operating voltage and the higher the amperage the better. Voltage × Amps will somewhat determine how much power your power supply will be able to supply when the amplifier is pulling the needed amperage.
Hi there, great video. Any suggestions on a bluetooth 5.1 decoder with bluetooth streamer, where i can use the ht21 as wireless rear receiver/amplifier?
Hello, maybe try the WUZHI ZK-PT2. It has 5.1 and 3.5mm aux in and out. www.ebay.com/itm/404494345324?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=qcyosggntfy&sssrc=4429486&ssuid=CxCvqTMMQZ2&var=&widget_ver=artemis&media=COPY
Sorry, I think I read your question wrong. You're wanting a 5.1 streamer device that will allow you to select the Wuzhi amp as bluetooth? I'm not too familiar with that kind of stuff, sorry. I think there is a product called the WiiM Pro? That may be something to look into, but as I said, I know nothing about streamers and stuff like that lol.
Maybe this aswell? I think this may be what you're looking for? But I am not sure. Hope some of this helps lol XDUOO XQ50 BT5.1 www.ebay.com/itm/195908639157?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=damjqec6rse&sssrc=4429486&ssuid=CxCvqTMMQZ2&var=&widget_ver=artemis&media=COPY
Hi, thanks a lot for videos. I don't wanna use a chinese app. Can you use any of these things without the app but just with the native Bluetooth connection?
@durrutino you'd have to Google each chip and compare. The 3255 would be more power..etc.. I think the 3251 has a miniscule amount less of THD. I don't think there is much of a Noticeable difference in the chips, besides power. It will depend on how the companies implement the chip though
compre el zk-ht21 y aunque tiene muy buena calidad el sonido me parecio que es baja su potencia, nada que ver con 160w por cana, usando 36v 10 amperios 3 ohms, iba a cambiarlo por el AS21... pero en base a tu recomendacion me quedo con el zk-ht21
The HT21 has better bass but the AS21 has better mids/highs. Overall I'd probably stay with the HT21 but there is nothing wrong with testing both, that's what I'd suggest.
@@scarr3ll I modified the ht21, I put a couple of 10,000 microfarad capacitors on it, I added a preamplifier by modifying the design, I increased the sound power a lot and I have more frequency range, greetings. modifique el ht21, le puse un par de capacitores de 10,000 microfaradios, le agregue un preamplificador modificando el diseño, incremento bastante el la potencia de sonido y tengo mas rango de frecuencias, saludos.
@@scarr3ll I tried with another power supply, same thing. I am currently using it with a dc 24V 10.4A LED transformer. Treble is very annoying when I open it.
i liked your video. i wonder if i can use my sppeakers from my stereo. it's 6 ohms and 150w rms. the model it's ss rg555 . it was a sony speakers that i had from my late bro, so i thought i use them. i guess i might but not using with high voltage power supply. well this is why i asking if possible.
Easily. Just hook power and ground up to the vehicle battery. You should probably add an inline fuse to the power wire also.. be sure to use a thick enough gauge wire, 8gauge cable should be OK since it's not pulling too much current. Then you need a distribution block to downsize cable to the amp safely. So, 8gauge power and ground to a fused power distribution block, and then a ground distribution block. This way you can safely go from 8g to 12g or so cable that will easily fit into the amp... You could do this a few other ways, but just be sure to use thick enough cable to carry the current over the length of cable you're using, so you don't melt/burn anything.
Saya punya zk tb 21 pemakaian hanya beberapa bulan bluetooth sudah rusak... dan saya lihat di youtube juga bayak keluan seperti saya... kenapa... ap itu kelemahan zk tb 21
Go with the HT21, and yes you can run these amps at 2ohm. If you want to run two 8"s, you need two dual 2ohm to wire to a final 2ohm impedance. Or just a single dual 4ohm. I'm currently using a dual 4ohm 8" sundown sa v3 wired to 2ohm on my ht21 and it thumps.
@@blackjack4l989 sorry just seen this while going over my videos. I know it's 3months later but it depends on how you connect the wires to the amp. If just bare wire, I'd say 16g. If you use connectors you could use maybe 14g or 12g if you can find connectors that small to still fit into the terminals. But really with the power these put out, 16g is plenty since these do not pull alot of current..etc
I have this amplifier ZK-HT21 i used psu 24V 5A and 4inch speaker 2x 60W 4ohm & 1 pair of Sony subwoofer 100W 4ohm ported box 5inch & the sound quality performance is awesome specially the sound quality of Bass is really impressive although my issues that i don't like this amplifier is the woman speaking when you tune the dial mode 😂 speaking Bluetooth mode 😂 USB mode 😆😆 is there a way to stop a woman speaking 😆
Only speakers larger than 4 ohms can be used with the HT21! If you use 2 ohms and apply power more than 20 volts tda7498e BURN !!! AS21 does not have such problems, but the sound quality is worse! Plays not a full set of low frequencies!
Fake review as21 is better it got a self protection the ht21 will burn instantly if you use the wrong impedance speaker like 2ohms not like the as21 it will just protect itself.
Развлечения
The apps input voltage function is used to set a limit on the volume knob. You set it like setting gains so you don’t have any clipping
I've got the HT21, a MeanWell 36V 10A power supply, 2 large 4-ohm Sony bookshelf speakers with 2 midranges and a horn tweeter in each, and a 10" DVC BOSS subwoofer wired to 2-ohm, and mounted in a Klipsch downfiring box... Lemme tell ya about "BLOW THE ROOF OFF"... This thing will rattle the neighbor's windows, and make your eyeballs vibrate in their sockets... It's got crystal-clear highs, and booming bass that sounds GREAT... I've bought several Aiyimas, and several smaller Wuzhis to install into hardwood cigar boxes to sell... But this one is the best so far... It's truly a BEAST...
Everyone always asks what amp is better. The ht21 or as21 and so on... I always tell them the HT21 is the all around best one
there are at least two versions of ZK-AS21 in the market. think you have the older version with TPA3251. they use TPA3255 for the newer ones. you can tell the difference by looking at the lower limit of the supply voltage. 12V is TPA3251 while 16V is TPA3255...
Thanks for the hint.
In the video footage, you can definitely see the voltage print 12v, so he got TPA3251 chip which doesn't have the power as in the TPA3255 model which is printed 16V-38V
Just a suggestion... Could you do a side by side of the 2 amps powering the same speakers? I appreciate that we don't get the same sound on RUclips as you do in person, but sometimes you can pick up on the difference in sound relative to each other. Just a thought
I may be able to do something like that soon. I bought some new speakers, a 600w power supply and another HT21 for backup just incase something ever happens. I still have the AS21 aswell, so once I get time I'll try and get a video up
@@scarr3ll Looking forward to it
Thanks so much for this review
Me too I got the ht21 and conected to it two sony hifi speakers and a 12 inch subwoofer that is rated 300w rms and It is flawless
I'm glad to hear this review good job
What If I was to get the other amp would it do good
Quick question with regards to the HT21: Does this board have a high pass filter for the tops ? Or is the stereo channel a fullrange signal (including bass)
...this would be worst case! And if there is a highpass: does the cutoff frequency go in sync with the frequency-potentiometer for the sub?
There is only a crossover for the subwoofer, but it doesn't really work lol. The sub channel on all of these mini amps, have vocal bleed. They are crossed around 200hz to begin with, and then the "crossover" filter does whatever from there, but you still have vocals coming through regardless, so it's kinda pointless lol. But if the sub isn't close to you, then it's not a huge deal but something to consider. And the mids/highs only have basic "treble/bass controls, no crossover for them. The treble/bass seem to effect each other also, so kind of have to find a happy medium. That's one of the downfalls of these mini amps, the lack of equalization can make it difficult to obtain a good sound at certain volumes, but overall they do sound good for basic needs. These aren't high end by any means but they have their place, good for basic home audio, garage setup/man cave, portable Bluetooth setups..etc.
Sir, this is my zk-ht21, I have a problem with the output of the R+R- channel on the speaker, there is only a loud bang and the speaker spull is hot. What do you think, sir??
These units aren't built very well, I would just buy a new amp and be done with it. One thing, DO NOT mess with the speaker outputs while the amp is on and playing music. Keep the amp off while wiring speakers up, and then turn it on.
@@scarr3ll ok,thank's sir..👍
I just want to ask about microphone input in it and if the voice quality and echo is good?
There is no dedicated mic input. Just a 3.5mm input and no echo controls. Only subwoofer, bass and high for speakers. They sound fine otherwise.
thanks. My newly bought HT21 has a large 60-90w power draw all the time, sending all that power as very low frequency hum to subwoofer so I'm returning it. I'm looking at TPA3255 amps but some reviews share your thoughts on the subwoofer weakness of the AS21
Yeah, ALL of the 3255 amps I've tried have to have the bass turned up quite a bit, unlike the ht21. But they still give plenty of bass once you do that. You might look into the Fosi Audio bt30d PRO, it's a little higher quality build 3255 amp, but lacks a fan, so you may need to disassemble the case and drill some holes, this will keep the amp much much cooler.
@@scarr3ll thanks. I'll into it! Pricey but I might be able to find a amp/board that is similar to this.
@@scarr3ll I found the Fosi and insanely cheap ($62 with PSU) alternative with similar specs. however, I wonder why the recommended power supply for these is 32V - 5 amps. Isn't that underpowered to max the Fosi Audio bt30d PRO?
@zodiacfml yeah, I think they just recommend a smaller power supply because it's cheaper, and most people just want sound right away and aren't worried about getting all the power they can if it's loud enough with the 5a supply.
@@scarr3ll I see, makes sense. I'm looking at this KGUSS PA8 that is the equivalent to the Fosi Audio BT30d pro or an Aiyima. Is the subwoofer/bass gain of the Fosi Audio as good or better than the ZK-HT21?
On witch one subwoofer sounds better? I have xh-a128 amplifier witch uses tda7498e and clearly can hear vocals from subwoofer (amp has no frequency adjustment pot). How these sound with sub. Witch one is better?
The HT21 is better over all. The AS21 requires the Wuzhi App and you have to adjust the eq and main volume of the app itself to adjust the sound of the amp, its weird.
Both amps still have vocal bleed. I believe ALL of these mini amps are crossed around 200hz or so. These may benefit being ran through an external eq or something for better control but by that point, you may aswell buy an actual receiver.
Sy Mao ber tanya sy punya m zk 21 kenapa app wuzhi audio ngak bisa di buka tolong imponya terima ksh
I have this KIT both, all ori from wuzhi audio. In App (for AS21), if equalizer set to flat or disable, I will definitely choose HT-21. But if equalizer set to more bass, i prefer AS21, because i think, L-R ch AS21 more and very clarity :D. Just my opinion. by the way, good review,sir.
Thank you. Check out their new stuff if you haven't. The AS21P and their TPA3251 2.1 amps. They look promising
What would it be an optimal power supply for the HT21 ?
I've been using a 36v 11amp switching power supply for a long while now and it is what I suggest. Use a voltage withing the amps operating voltage and the higher the amperage the better. Voltage × Amps will somewhat determine how much power your power supply will be able to supply when the amplifier is pulling the needed amperage.
Hi there, great video. Any suggestions on a bluetooth 5.1 decoder with bluetooth streamer, where i can use the ht21 as wireless rear receiver/amplifier?
Hello, maybe try the WUZHI ZK-PT2.
It has 5.1 and 3.5mm aux in and out.
www.ebay.com/itm/404494345324?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=qcyosggntfy&sssrc=4429486&ssuid=CxCvqTMMQZ2&var=&widget_ver=artemis&media=COPY
Sorry, I think I read your question wrong. You're wanting a 5.1 streamer device that will allow you to select the Wuzhi amp as bluetooth? I'm not too familiar with that kind of stuff, sorry. I think there is a product called the WiiM Pro? That may be something to look into, but as I said, I know nothing about streamers and stuff like that lol.
Maybe this aswell? I think this may be what you're looking for? But I am not sure. Hope some of this helps lol
XDUOO XQ50 BT5.1
www.ebay.com/itm/195908639157?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=damjqec6rse&sssrc=4429486&ssuid=CxCvqTMMQZ2&var=&widget_ver=artemis&media=COPY
Hi, thanks a lot for videos. I don't wanna use a chinese app. Can you use any of these things without the app but just with the native Bluetooth connection?
Yes. I've been messing with both without the app and you can get quality sound without the app. I prefer without the app myself
@@scarr3ll but I take from your opinion that ht21 sounds tad better?
ZK-AS21, YS-AS21 diferences?
No difference. Same board, just sold under a different brand. Same as the Wuzhi and Xinyi amps..etc
Ok, thanks!. The question that remains whether or not the TPA3255 improves subwoofer output compared to the TPA3251, or has nothing to do with it...
@durrutino you'd have to Google each chip and compare. The 3255 would be more power..etc.. I think the 3251 has a miniscule amount less of THD. I don't think there is much of a Noticeable difference in the chips, besides power. It will depend on how the companies implement the chip though
Yes, It will be a matter of seeing more comparisons and analysis. Very kind, thank you for your time.
How would this sound on an 18v drill battery? As I run all my class d amps off of them
Please watch my video on "extremely loud portable Bluetooth speaker" using a 2ch version of the tda7498
ruclips.net/video/lr0O073a--g/видео.html
sir can i ask if i can connect the 2 pcs of 8 ohms dual coil sub and parallel it into 4 ohms to ht21 amp ?
4ohm is fine. Anything below 2ohm the amp won't like
Posso ligar nele 2 driver e 2 agudo jogando pra ele os cortes do processador de áudio
compre el zk-ht21 y aunque tiene muy buena calidad el sonido me parecio que es baja su potencia, nada que ver con 160w por cana, usando 36v 10 amperios 3 ohms, iba a cambiarlo por el AS21... pero en base a tu recomendacion me quedo con el zk-ht21
The HT21 has better bass but the AS21 has better mids/highs. Overall I'd probably stay with the HT21 but there is nothing wrong with testing both, that's what I'd suggest.
@@scarr3ll I modified the ht21, I put a couple of 10,000 microfarad capacitors on it, I added a preamplifier by modifying the design, I increased the sound power a lot and I have more frequency range, greetings.
modifique el ht21, le puse un par de capacitores de 10,000 microfaradios, le agregue un preamplificador modificando el diseño, incremento bastante el la potencia de sonido y tengo mas rango de frecuencias, saludos.
10k microfarad, what voltage sir@@user-xw7no3to2e
Does the as21 work good?
Go with the HT21 over the AS21
@@scarr3ll ok
Hello. I also use this amp. When I turn on treble, there is an annoying static noise. how do i solve this problem
Try a different power supply
@@scarr3ll I tried with another power supply, same thing. I am currently using it with a dc 24V 10.4A LED transformer. Treble is very annoying when I open it.
This circuit has an annoying Chinese language when starting up, can the app be turned off?
No, the voice feature cannot be turned off unfortunately.
i liked your video. i wonder if i can use my sppeakers from my stereo. it's 6 ohms and 150w rms. the model it's ss rg555 . it was a sony speakers that i had from my late bro, so i thought i use them. i guess i might but not using with high voltage power supply. well this is why i asking if possible.
Yes 6ohm speakers are fine, they'll just get a little less power than they would at 4ohm..etc
So for a subwoofer amplifier running a 10 inch subwoofer? Any reply appreciated! Cheers from Australia 🙂
The HT21 will run a 10 or 12 subwoofer no probldm
How to use in 12v car battery
Easily. Just hook power and ground up to the vehicle battery. You should probably add an inline fuse to the power wire also.. be sure to use a thick enough gauge wire, 8gauge cable should be OK since it's not pulling too much current. Then you need a distribution block to downsize cable to the amp safely.
So, 8gauge power and ground to a fused power distribution block, and then a ground distribution block. This way you can safely go from 8g to 12g or so cable that will easily fit into the amp...
You could do this a few other ways, but just be sure to use thick enough cable to carry the current over the length of cable you're using, so you don't melt/burn anything.
thank
Is it Quick review? Almost 11 mins.
Hello. When connected to bluetooth, is there a female voice that the phone is connected? HT21
Yes. It says "bluetooth mode"
Saya punya zk tb 21 pemakaian hanya beberapa bulan bluetooth sudah rusak... dan saya lihat di youtube juga bayak keluan seperti saya... kenapa... ap itu kelemahan zk tb 21
I never had a problem with my tb21, nor any of the Wuzhi amps. I am sorry.
Beli yg ori wuzhi audio. Aman 🤭😁
Thinking of 2ohm tho
Go with the HT21, and yes you can run these amps at 2ohm. If you want to run two 8"s, you need two dual 2ohm to wire to a final 2ohm impedance. Or just a single dual 4ohm. I'm currently using a dual 4ohm 8" sundown sa v3 wired to 2ohm on my ht21 and it thumps.
@@scarr3ll ok cool thanks bro
@@scarr3ll what's the biggest gauge wire was you able to fit in the ht21 amp
@@blackjack4l989 sorry just seen this while going over my videos. I know it's 3months later but it depends on how you connect the wires to the amp. If just bare wire, I'd say 16g. If you use connectors you could use maybe 14g or 12g if you can find connectors that small to still fit into the terminals. But really with the power these put out, 16g is plenty since these do not pull alot of current..etc
My dude talks a bit too much. It's more than 10 minutes, not 5 minutes. Anyway, thanks my dude.😅
I have this amplifier ZK-HT21 i used psu 24V 5A and 4inch speaker 2x 60W 4ohm & 1 pair of Sony subwoofer 100W 4ohm ported box 5inch & the sound quality performance is awesome specially the sound quality of Bass is really impressive although my issues that i don't like this amplifier is the woman speaking when you tune the dial mode 😂 speaking Bluetooth mode 😂 USB mode 😆😆 is there a way to stop a woman speaking 😆
Lol yeah the voice can be annoying. It's programmed into the chip, so no way to turn it off unfortunately lol
Only speakers larger than 4 ohms can be used with the HT21! If you use 2 ohms and apply power more than 20 volts tda7498e BURN !!!
AS21 does not have such problems, but the sound quality is worse! Plays not a full set of low frequencies!
That's not true lol. I literally run the HT21 at 2ohm full volume on ALL CHANNELS at 40volt!!
@@scarr3ll tôi có HT21 bản nâng cấp Bluetooth, chơi loa sub 2 ohms 200w ở điện áp 32v thì có vấn đề gì không?
Fake review as21 is better it got a self protection the ht21 will burn instantly if you use the wrong impedance speaker like 2ohms not like the as21 it will just protect itself.
What? I run the ht21 at 2ohm ON ALL CHANNELS AT FULL VOLUME. NO ISSUES
Moi je crois que c'est vous qui êtes nul !! ho ça oui !!!!!
May your mother live with a flea infestation on her vagina.
@@scarr3ll Poor boy, so useless that he becomes vulgar.
You know I’m gonna report your rude response and shut down your crappy network? .......
@@scarr3ll hahahaa 😂😂😂😂 dude shoutout next upload
@@scarr3ll hahahahhaha
zk-as21
👇