Hey, just found a solution on yt, the horrible freq resp is because the input caps, removing c41-42 fix the hi-freq rollof, increasing the c37-39 from 100n to 500n-1u will improve the bass.
Yay! Not bothered by your timing at all, I'm glad you decided to try it out! I was just about to write a review for them, and this might help. Also, I'm snaking our house drain today, and it's really shitty, so this helped make my day better! Thank you!
Much thanks! Too bad it wasn't any good. I used to have to blow out my house drain line with one of those rubber bladder things. It finally got so bad, I had to hire a plumber to dig up the yard to install a new line.
@@JohnAudioTech yeah the house we're renting is from the 20's so at some point it needs to happen, but you can bet the landlord doesn't wanna drop the dough. The house is what they call a "scrape job" Anyhow, thanks for looking into this unit. You couldn't see it since your woofers have that lattice over them, but when i turn the volume knob the woofers move in and out. I assume that means there's some DC at the outputs that shouldn't be there? Also, if I leave the volume up but stop the music, there's a bunch of nasty noise that comes up after a few seconds of silence (when using the 3.5mm input). As soon I press play it goes away, or if I connect it to Bluetooth. They suggested a shielded aux cable but I tried several cables with no change, so I reckon either the unit itself is too close to my computer (which shielding would address probably) or the layout of the traces with signal passing right by the always-on bluetooth module is to blame. Anyhow, good enough to listen through some thriftstore speakers, but I won't be hooking up the wharfedale's or energy's to this thing.
I have that same little amp in the bedroom that I use for listening to podcasts before bed. I did notice the highs and lows are a bit subdued but I've got it driving a pair of satellite speakers with no sub so they compliment each others lousy frequency response. I also noticed the BT will stay paired to my phone no matter how you've got the power switch so it's normal, at least for this board.
These chips, from what I understand, are sorted products. The units that don't quite make the grade, get sold off under no name brands for super cheap. I have a BT-Wuzhi TPA3116D2, but mine is the version with 5 poly caps and has an aggressive 5.0 Bluetooth connection.
I have the same amplifier, I bought it specifically for the swing input voltage, as it'll be run off a 4s3p 18650 Lion pack... Nowhere in my documentation does it require me to "match speakers" (#7 in your documentation) and limit the input supply for a 4 ohm load to 12v. I DO have a few BT 2x20w amps that do have this requirement... And I mainly use them to push audio into visualizers, so I've never really cared... Let's test this *EDIT* = so I pushed 16.8v into the amplifier (to simulate a 4s Lion pack), on a 2x 4ohm load. After about a .9a draw from a constant current source, I could hear the speakers clipping, and the osc proved it. FWIW, the speakers are small 3.5" full-range units, rated for 4ohm and ~25w... At 12.6v, I can pull 1.8a before I bottom out, though the signal seems okay, and it's a limit of my 25w drivers. This wasn't with a 1000hz tone, this was with actual music. I need to put my signal gen together before I can do that, and I'm not putting a 13$ Aliexpress amplifier on my rack - My phone signal gen puts out too many harmonics to be useful. I'll update, again, in a bit. BTW - new sub - THANK you for these Aliexpress reviews. I've been taking PAGES of notes, including osc. reads since I started buying these boards 2 years ago - if you have any questions yourself, send them my way. EDIT: what's your thought on a reactive type speaker load tester, rather than a simple high wattage resistor, for testing? Necessary with an oscilloscope?
Thank you so much for your information, I have a question for you, have you ever tested the ap3050d chip?? It seems to be the generic form the Tpa3116... Let me know if you think these 2 chips can be pushed all the way to 24v on 4 ohms speakers, thank you
I've got one of these. It's perfect for a garage workbench sound system, where mower maintenance is the focus. The heatsink is almost adequate for what this amp can do, which isn't much. The word "Anemic" comes to mind. It probably just needs braided silver speaker wires. /s
Man I love these videos. Very thorough testing. I just ordered the zk-1002 I hope that wasn't a mistake. Im wanting to build a portable boom box that can run off battery or plug in. It has to have Bluetooth. What amp would you suggest? I have access to free lithium batteries and power supplies that my job throws away so voltage won't be a problem. I'd like a decent power output to maybe drive 4ohm 6x9s or a 6.5 component set. So 100watts per channel is desired.
Hello John, Better late than never, was getting a new ISP, back on line now. Great review featuring Snickers. The reviews sure help to know what to get and what not to. Glad your doing well, I hope your Brother is too. Looking forward to more JAT videos as you are able. All the best from Oregon, C.
20:00 This is normal, and also pretty useful. Bluetooth is used for audio mostly in cars and earphones, so you want there instant, automatic connection with your phone. About heatsink - i think they could get away with using such a small one, but this would need really good pcb layout. Huge copper plane could easily dissipate ~5W, keeping amp ic well within its limits. But in this case i doubt it is good enough. Could this rolloff at ~4kHz be caused by audio out from bluetooth chip directly connected in parallel to the aux? If this is a case, then bt shouldn't have this problem, and for aux it can be solved with a simple switch.
@Badr Ahmed Probably yes, but you risking destroying bluetooth chip and/or poor audio quality. The best way to do that would be cutting signal tracks on pcb and using physical switch as an input selector.
Thanks so much for the review! Do you have a recommendation for something similar? I was thinking it would be great in a classic car in that kind of form factor
"John Audiotech Channel, I Dunno he's kinda weird " I think your wrong there, I've just found the guys channel and I think it's amazing ! very cool teaching style and he's tutorials rate among the best i've found ( and i've looked ! ) so go and check him out again, you'll learn ton's...LOL!...cheers.
How would you estimate how much waste heat a class-D amplifier needs to dissipate - and therefore how big a heat-sink you would need? Is there an efficiency ratio in the data sheet that you could use?
he's using the wrong measurements. Frenquency response in audio is going to be mostly determines by your speakers. BTW a $20 ebay amp now is going to be 1000 x better than a 70's $10,000 amp..
@@charlesreid9337 not really. The amplifier has its own frequency response and if it is like this one, you can feed it whatever signal you want but that won't ever come to your speakers because the amplifier/preamplifier is cutting certain range of frequencies
Very nice receivers from the 90s and 2000s are cheap used. Are these little dinky boards without a proper filtered power supply and heatsink really worth it?
There are some decent ones that you can buy at the usual suspects but don't buy the really cheap ones. The cheap ones will always have issues (that you can fix by soldering different decoupling caps, changing the input gain, ...). FFcossag also has some good videos on this subject: ua-cam.com/video/C_f8MYqeevQ/v-deo.html ua-cam.com/video/16k4goWRT4o/v-deo.html They are really nice if space is at a premium or you want to run them on batteries for using them outside.
Check the size and weight of an old 25W/ch receiver, and compare to this. These small chip amp boards are not intended for HiFi, but rather for small size and low cost.
I got 5 stamp size 5 volt amp boards and love the way they sound. The PAM8403 ...These one dollar wonders are rated 3watt/ stereo and run 3.5 to 5.1 volts. They stay cool and sound really good to my ears! That low sounding power output, 3 watts, delivers more than I ever thought. I have auditioned 5 or six of these class D amps and the PAM8403 is a HiFi wonder ! P.S. Don't exceed 5.2 volts, these things overheat-shut of on safety-may not be the same if they do come back on ........
According to datasheet of tpa3116, it's a 50 + 50 Watts stereo chip but your videos on this chip shows 50 Watts mono as well as stereo in the videos. Is it the same chip on both videos with one used as mono channel and other as stereo ? Why the mono version is called tpa3116 d2 while the stereo one tpa3116 when the datasheet calls it tpa3116d2 ?
Icluding an adequate heatsink would propably cost them more than the board itself. In my experience, thle little tpa3118 mono 50w board is the best, the bottom layer is all copper and is concected to the bottom powerpad of the chip, just cut a 1mm thermalpad that's the size of the board and slap it on any heatsink you want, since it's all smd, and there are no leads poking out the bottom. Oh an they are very cheap, just 1-2$ 🙂
Hi john. I got the same amp. But its 100x2. Can you help me? Because, mine always turned off automatically when i play music longer. I used 24v. Is it the IC getting hot that's why it's turned off or, my power supply (6amp) are tripping?
I was using a dewalt battery and it drained it down almost broke it I added a low voltage shut of switch and works but the low voltage switch still runs so I’m just going to add a on off switch
Hello John, I was wondering if you came through the crazy wind storm that impacted several states, including Ohio ok. I hope all is good with you. Two 100 degree days in a row here in Oregon, today, 8-16 cooled off quick with clouds and wind. Be good, C.
I have been running a TDA7498E (built in fan) into 2 x 15" 15 Ohm Tannoy's (ex BBC type) for around 2 years now. I also have a 2 Mullard 20 20 Watt valve amp I made about 50 years ago with the 3 valve pre amps. I don't think you can get a more different setup between those two. My ears are not what they were of course but I was plesantly surprised how well a few of the TDA and TPA perform. All in all I have around 8 TPA and TDA. Providing you set the gain (if available) correctly and pick the right one they are worth the money. I always drop a few volts from the max and run a small fan at 8V. They seen to like 15 Ohm's. This ones OK - I did the mod. :- ua-cam.com/video/44nTirZNFfk/v-deo.html
Hi John, thanks for your time. I had the same experience with Wuzhi amplifier, you can read here: hackaday.io/project/168919-3d-printed-bluetooth-speakers-littlejet/log/173573-the-amplifier Anyway, the frequency response from the Bluetooth is flat till around 19kHz (it's pretty common on Bluetooth ), then something is wrong on the input stage from cable: maybe those 2 capacitors or the chip itself (yes, the chip manage the input signal too)
The input capacitors can compromize the low frequency response what they also do for this amplifier. Normally my amplifiers roll off around 10 Hz. It is definitely not normal for an audio amplifier to roll off allready above 2 kHz. There is obviously something terribly wrong with this amplifier circuit.
i have a feeling the capacitors causing the low frequency rolloff are much deeper in the circuit (under the heatsink). i tried soldering an aux input directly to the volume pot to bypass the lpf cap filters and chip and it sounds much better! but low frequency rolloff still exists!!!
@Davide Ercolano I found the solution for the frequency problem from your pages comments section, written by Claudio Silva. That mod worked for me, that aux input part looks equal to this Wuzhi board also. Thanks Claudio! Claudio Silva wrote 07/22/2020: Hi Davide, regarding WUZHI AUDIO ZK-1002 board I have notice exactly the same issue on the line In input. yesterday I have analysed the circuit and found that the problem is due capacitor C41 and C42 that are connecting que input signal after pass through a resistor to a ground before connect to the bluetooth IC. I have just removed these capacitors and surprise, now the sound is full of bright.
@@changtraidoc found it on Amazon but had to cut it almost in half with a hacksaw for it to fit. Also had to bend one of the discarded fins into a rectangle to make a riser
I have the ZK-502T its bigger brother, but im not pleased with the bluetooth connection: whenever there is no audio playing the bluetooth goes into standby, also when you play music or a video and theres a quiet part the bluetooth also goes into standby mode and pops buzzes after the quiet part is over and sound is active again.( Theres also a long delay in the audio making it not suitable for watching videos over bluetooth The sound is a bit thin metallic robotic over bluetooth theres also digital noise whenever bluetooth is active or when the aux port is active you can hear a hiss/hum plus loud pops woofer flexin mad when you move the aux cable to much (i have a decent quality aux cable/even has magnets on them) I bought 2 of these ZK-502T amps, gues i wasted my money. Hope the nobsound NS-10G doesnt have this bluetooth problem. Edit: I have been advised to search for amps that use this bluetooth chip it doesnt have the sound dropout problem Qualcomm QCC3003
Did not like the sound quality of this amp. Hard to tell over UA-cam and all but I hear intermodulation distortion between vocal and instrument tracks. First time an amp really tweeked my ears so bad right at the get go...Thanx JAT !!!!
I have had better results with bluetooth. Cus i am a lazy man and not interested in fixing circuit designs. My speaker makes 50hz noise when i use a audio cable & thats why i use the bluetooth mode & my pc has a wifi 6 card with bluetooth 5.0 so it sounds pretty good tbh. I mean i cant find a difference.. my pc can output some 294khz at 32bit sample rate which is totally unnecessary! Human ear can not differentiate anything above 20bit .. so 24bit bluetooth audio is pretty good enough unless u editing movies & really want to hear every single note accurately!
With bt i would worry not for audio quality, but for latency. Try lifting ground of your amp/speakers (something like foil bag around earth pin in a plug). If this wold work, simple ground loop insulator will do the trick.
@@michamaecki8104 even the latency is not noticeable unless i move my speaker to like 5 or 6m .. & the buzz goes away if i power the speaker with a usb charger but i am too lazy to turn on another switch so i keep it plugged into my monitor & it powers on when my pc sends a wake-up signal to the monitor 😂.
@@johncoops6897 yes the sound does not lag behind the video or whatever is playing on screen. Although i do not have any scientific testing tool to measure that ..
Thanks for the video. I used another version of this board in a recent (very strange) project and got great results. I tested the board for output power as well. Video link if anyone’s interested: ua-cam.com/video/JPrklV3l5yw/v-deo.html
I think youre using the wrong measurement system. Youre definitely using the wrong voltage. Id really suggest you use a 24v power supply (youre an electronics geek why arent you using a bench supply at 24v??) and id suggest you compare your amps through a standard >quality< speaker.
The TPA3116 is good for a class D, as far as clean low distortion power goes, as long as it has good complimentary components. Switched my living room setup over after my speaker amp fried all it's transistors one day as a temporary, and was pleasantly surprised.
Hey, just found a solution on yt, the horrible freq resp is because the input caps, removing c41-42 fix the hi-freq rollof, increasing the c37-39 from 100n to 500n-1u will improve the bass.
Any link?
Yay! Not bothered by your timing at all, I'm glad you decided to try it out! I was just about to write a review for them, and this might help.
Also, I'm snaking our house drain today, and it's really shitty, so this helped make my day better! Thank you!
Much thanks! Too bad it wasn't any good. I used to have to blow out my house drain line with one of those rubber bladder things. It finally got so bad, I had to hire a plumber to dig up the yard to install a new line.
@@JohnAudioTech yeah the house we're renting is from the 20's so at some point it needs to happen, but you can bet the landlord doesn't wanna drop the dough. The house is what they call a "scrape job"
Anyhow, thanks for looking into this unit. You couldn't see it since your woofers have that lattice over them, but when i turn the volume knob the woofers move in and out. I assume that means there's some DC at the outputs that shouldn't be there? Also, if I leave the volume up but stop the music, there's a bunch of nasty noise that comes up after a few seconds of silence (when using the 3.5mm input). As soon I press play it goes away, or if I connect it to Bluetooth. They suggested a shielded aux cable but I tried several cables with no change, so I reckon either the unit itself is too close to my computer (which shielding would address probably) or the layout of the traces with signal passing right by the always-on bluetooth module is to blame.
Anyhow, good enough to listen through some thriftstore speakers, but I won't be hooking up the wharfedale's or energy's to this thing.
I have that same little amp in the bedroom that I use for listening to podcasts before bed. I did notice the highs and lows are a bit subdued but I've got it driving a pair of satellite speakers with no sub so they compliment each others lousy frequency response. I also noticed the BT will stay paired to my phone no matter how you've got the power switch so it's normal, at least for this board.
These chips, from what I understand, are sorted products. The units that don't quite make the grade, get sold off under no name brands for super cheap. I have a BT-Wuzhi TPA3116D2, but mine is the version with 5 poly caps and has an aggressive 5.0 Bluetooth connection.
I have the same amplifier, I bought it specifically for the swing input voltage, as it'll be run off a 4s3p 18650 Lion pack... Nowhere in my documentation does it require me to "match speakers" (#7 in your documentation) and limit the input supply for a 4 ohm load to 12v. I DO have a few BT 2x20w amps that do have this requirement... And I mainly use them to push audio into visualizers, so I've never really cared...
Let's test this
*EDIT* = so I pushed 16.8v into the amplifier (to simulate a 4s Lion pack), on a 2x 4ohm load. After about a .9a draw from a constant current source, I could hear the speakers clipping, and the osc proved it. FWIW, the speakers are small 3.5" full-range units, rated for 4ohm and ~25w... At 12.6v, I can pull 1.8a before I bottom out, though the signal seems okay, and it's a limit of my 25w drivers. This wasn't with a 1000hz tone, this was with actual music. I need to put my signal gen together before I can do that, and I'm not putting a 13$ Aliexpress amplifier on my rack - My phone signal gen puts out too many harmonics to be useful. I'll update, again, in a bit.
BTW - new sub - THANK you for these Aliexpress reviews. I've been taking PAGES of notes, including osc. reads since I started buying these boards 2 years ago - if you have any questions yourself, send them my way.
EDIT: what's your thought on a reactive type speaker load tester, rather than a simple high wattage resistor, for testing? Necessary with an oscilloscope?
Thank you so much for your information, I have a question for you, have you ever tested the ap3050d chip?? It seems to be the generic form the Tpa3116... Let me know if you think these 2 chips can be pushed all the way to 24v on 4 ohms speakers, thank you
I've got one of these. It's perfect for a garage workbench sound system, where mower maintenance is the focus. The heatsink is almost adequate for what this amp can do, which isn't much. The word "Anemic" comes to mind. It probably just needs braided silver speaker wires. /s
Man I love these videos. Very thorough testing. I just ordered the zk-1002 I hope that wasn't a mistake. Im wanting to build a portable boom box that can run off battery or plug in. It has to have Bluetooth. What amp would you suggest? I have access to free lithium batteries and power supplies that my job throws away so voltage won't be a problem. I'd like a decent power output to maybe drive 4ohm 6x9s or a 6.5 component set. So 100watts per channel is desired.
Hello John, Better late than never, was getting a new ISP, back on line now. Great review featuring Snickers. The reviews sure help to know what to get and what not to. Glad your doing well, I hope your Brother is too. Looking forward to more JAT videos as you are able. All the best from Oregon, C.
20:00 This is normal, and also pretty useful. Bluetooth is used for audio mostly in cars and earphones, so you want there instant, automatic connection with your phone.
About heatsink - i think they could get away with using such a small one, but this would need really good pcb layout. Huge copper plane could easily dissipate ~5W, keeping amp ic well within its limits. But in this case i doubt it is good enough.
Could this rolloff at ~4kHz be caused by audio out from bluetooth chip directly connected in parallel to the aux? If this is a case, then bt shouldn't have this problem, and for aux it can be solved with a simple switch.
@Badr Ahmed Probably yes, but you risking destroying bluetooth chip and/or poor audio quality. The best way to do that would be cutting signal tracks on pcb and using physical switch as an input selector.
Thanks so much for the review! Do you have a recommendation for something similar? I was thinking it would be great in a classic car in that kind of form factor
I don't know who John is, but I know SnickerAudioTech channel and his minion doing the review. :D
That frequency response almost looked kinda like a phono equalization.
"John Audiotech Channel, I Dunno he's kinda weird " I think your wrong there, I've just found the guys channel and I think it's amazing ! very cool teaching style and he's tutorials rate among the best i've found ( and i've looked ! ) so go and check him out again, you'll learn ton's...LOL!...cheers.
How would you estimate how much waste heat a class-D amplifier needs to dissipate - and therefore how big a heat-sink you would need? Is there an efficiency ratio in the data sheet that you could use?
The datasheet will often show the efficiency. Usually around 10% of max power is turned into heat not counting losses in the coils.
isthere a soluiton to get rid of that buzzing ? is it related to the bluetooth ? if it is so if you removethe bluetooth chip it could stop buzzing ?
Well you answered my question. I was wondering what the freq response was on these things. Definitely not HIFI!!!!!!
he's using the wrong measurements. Frenquency response in audio is going to be mostly determines by your speakers. BTW a $20 ebay amp now is going to be 1000 x better than a 70's $10,000 amp..
@@charlesreid9337 not really. The amplifier has its own frequency response and if it is like this one, you can feed it whatever signal you want but that won't ever come to your speakers because the amplifier/preamplifier is cutting certain range of frequencies
Very nice receivers from the 90s and 2000s are cheap used. Are these little dinky boards without a proper filtered power supply and heatsink really worth it?
There are some decent ones that you can buy at the usual suspects but don't buy the really cheap ones. The cheap ones will always have issues (that you can fix by soldering different decoupling caps, changing the input gain, ...). FFcossag also has some good videos on this subject:
ua-cam.com/video/C_f8MYqeevQ/v-deo.html
ua-cam.com/video/16k4goWRT4o/v-deo.html
They are really nice if space is at a premium or you want to run them on batteries for using them outside.
Check the size and weight of an old 25W/ch receiver, and compare to this. These small chip amp boards are not intended for HiFi, but rather for small size and low cost.
I got 5 stamp size 5 volt amp boards and love the way they sound. The PAM8403 ...These one dollar wonders are rated 3watt/ stereo and run 3.5 to 5.1 volts. They stay cool and sound really good to my ears! That low sounding power output, 3 watts, delivers more than I ever thought. I have auditioned 5 or six of these class D amps and the PAM8403 is a HiFi wonder ! P.S. Don't exceed 5.2 volts, these things overheat-shut of on safety-may not be the same if they do come back on ........
According to datasheet of tpa3116, it's a 50 + 50 Watts stereo chip but your videos on this chip shows 50 Watts mono as well as stereo in the videos. Is it the same chip on both videos with one used as mono channel and other as stereo ? Why the mono version is called tpa3116 d2 while the stereo one tpa3116 when the datasheet calls it tpa3116d2 ?
Icluding an adequate heatsink would propably cost them more than the board itself. In my experience, thle little tpa3118 mono 50w board is the best, the bottom layer is all copper and is concected to the bottom powerpad of the chip, just cut a 1mm thermalpad that's the size of the board and slap it on any heatsink you want, since it's all smd, and there are no leads poking out the bottom. Oh an they are very cheap, just 1-2$ 🙂
Hi john. I got the same amp. But its 100x2. Can you help me? Because, mine always turned off automatically when i play music longer. I used 24v. Is it the IC getting hot that's why it's turned off or, my power supply (6amp) are tripping?
What is the song at 7:30
Mendelsons is having a liquidation sale, banana boxes you can fill up all you want for $20!
I was using a dewalt battery and it drained it down almost broke it
I added a low voltage shut of switch and works but the low voltage switch still runs so I’m just going to add a on off switch
Are you always suppose to use a dummy load while testing the amp?
Hello John, I was wondering if you came through the crazy wind storm that impacted several states, including Ohio ok. I hope all is good with you. Two 100 degree days in a row here in Oregon, today, 8-16 cooled off quick with clouds and wind. Be good, C.
Can you use TPA-3116 without inductors?
I have been running a TDA7498E (built in fan) into 2 x 15" 15 Ohm Tannoy's (ex BBC type) for around 2 years now. I also have a 2 Mullard 20 20 Watt valve amp I made about 50 years ago with the 3 valve pre amps. I don't think you can get a more different setup between those two. My ears are not what they were of course but I was plesantly surprised how well a few of the TDA and TPA perform. All in all I have around 8 TPA and TDA. Providing you set the gain (if available) correctly and pick the right one they are worth the money. I always drop a few volts from the max and run a small fan at 8V. They seen to like 15 Ohm's. This ones OK - I did the mod. :-
ua-cam.com/video/44nTirZNFfk/v-deo.html
Is it possible to mod it to boost those frequencies?
I have the same question...
Wouls you please do the same tests with 24V of supply voltage?
I would be very thankfull.
ImaginaPower, should work, but will kill the caps fast.
Will you try This one TPA3116D2 120Wx2 I want to know is it worth the money. Thanks !
Have you tested the TPA6120 chip yet ?
Može koja shema Tda ili Lm pojačala u A klasi?? I da bude u Hi-fi
Hi John, thanks for your time.
I had the same experience with Wuzhi amplifier, you can read here: hackaday.io/project/168919-3d-printed-bluetooth-speakers-littlejet/log/173573-the-amplifier
Anyway, the frequency response from the Bluetooth is flat till around 19kHz (it's pretty common on Bluetooth ), then something is wrong on the input stage from cable: maybe those 2 capacitors or the chip itself (yes, the chip manage the input signal too)
The input capacitors can compromize the low frequency response what they also do for this amplifier. Normally my amplifiers roll off around 10 Hz. It is definitely not normal for an audio amplifier to roll off allready above 2 kHz. There is obviously something terribly wrong with this amplifier circuit.
@@gkdresden but, again, the problem is in the first stage between the aux jack and the bluetooth chip, till inside of this last one of course
i have a feeling the capacitors causing the low frequency rolloff are much deeper in the circuit (under the heatsink). i tried soldering an aux input directly to the volume pot to bypass the lpf cap filters and chip and it sounds much better! but low frequency rolloff still exists!!!
@Davide Ercolano I found the solution for the frequency problem from your pages comments section, written by Claudio Silva. That mod worked for me, that aux input part looks equal to this Wuzhi board also. Thanks Claudio!
Claudio Silva wrote 07/22/2020:
Hi Davide, regarding WUZHI AUDIO ZK-1002 board I have notice exactly the same issue on the line In input.
yesterday I have analysed the circuit and found that the problem is due capacitor C41 and C42 that are
connecting que input signal after pass through a resistor to a ground before connect to the bluetooth IC.
I have just removed these capacitors and surprise, now the sound is full of bright.
Heatsink is pretty expensive ! Costs more than IC itself.
drive.google.com/file/d/1vxYHfHtItwUPasMQAUdA9D9Tgh3dRufY/view?usp=drivesdk
@@draztiqmeshaz6226 How can i find heatsink like that?
@@changtraidoc found it on Amazon but had to cut it almost in half with a hacksaw for it to fit. Also had to bend one of the discarded fins into a rectangle to make a riser
Lol I’m actually listening to this on that now.
Seems to me it's best to use a much better heat sink
I did this with one of mine, and it helps, especially with harder-to-drive speakers
I have the ZK-502T its bigger brother, but im not pleased with the bluetooth connection: whenever there is no audio playing the bluetooth goes into standby, also when you play music or a video and theres a quiet part the bluetooth also goes into standby mode and pops buzzes after the quiet part is over and sound is active again.( Theres also a long delay in the audio making it not suitable for watching videos over bluetooth
The sound is a bit thin metallic robotic over bluetooth theres also digital noise whenever bluetooth is active or when the aux port is active you can hear a hiss/hum plus loud pops woofer flexin mad when you move the aux cable to much (i have a decent quality aux cable/even has magnets on them)
I bought 2 of these ZK-502T amps, gues i wasted my money.
Hope the nobsound NS-10G doesnt have this bluetooth problem.
Edit: I have been advised to search for amps that use this bluetooth chip it doesnt have the sound dropout problem
Qualcomm QCC3003
What song was that?
5:26 anyone know what amp that is?
Did not like the sound quality of this amp. Hard to tell over UA-cam and all but I hear intermodulation distortion between vocal and instrument tracks. First time an amp really tweeked my ears so bad right at the get go...Thanx JAT !!!!
Sir can we make asymmetrical amplifier in upper amplitude is larger than lower of a wave ?
Many companies make them by accident. It's called a "fault".
@@johncoops6897 thank u sir
Compression and expansion audio devices and programs can deliver most any gain curve you desire ...
@@coilsmoke2286 thank u sir
@@coilsmoke2286 thank u sir
Hello boss.. Pwde speaker 200watts?
Please suggest me best tone control for tda 7294
"Guitar Preamp" in Elektor's 301 Circuits. Good for home use. Apply OPA2134 opAmp.
I have had better results with bluetooth. Cus i am a lazy man and not interested in fixing circuit designs. My speaker makes 50hz noise when i use a audio cable & thats why i use the bluetooth mode & my pc has a wifi 6 card with bluetooth 5.0 so it sounds pretty good tbh. I mean i cant find a difference.. my pc can output some 294khz at 32bit sample rate which is totally unnecessary! Human ear can not differentiate anything above 20bit .. so 24bit bluetooth audio is pretty good enough unless u editing movies & really want to hear every single note accurately!
With bt i would worry not for audio quality, but for latency. Try lifting ground of your amp/speakers (something like foil bag around earth pin in a plug). If this wold work, simple ground loop insulator will do the trick.
@@michamaecki8104 even the latency is not noticeable unless i move my speaker to like 5 or 6m .. & the buzz goes away if i power the speaker with a usb charger but i am too lazy to turn on another switch so i keep it plugged into my monitor & it powers on when my pc sends a wake-up signal to the monitor 😂.
@@KuntalGhosh - latency is DELAY. When playing video, the sound lagging behind the vision.
@@johncoops6897 yes the sound does not lag behind the video or whatever is playing on screen. Although i do not have any scientific testing tool to measure that ..
Thanks for the video. I used another version of this board in a recent (very strange) project and got great results. I tested the board for output power as well. Video link if anyone’s interested: ua-cam.com/video/JPrklV3l5yw/v-deo.html
I think youre using the wrong measurement system. Youre definitely using the wrong voltage. Id really suggest you use a 24v power supply (youre an electronics geek why arent you using a bench supply at 24v??) and id suggest you compare your amps through a standard >quality< speaker.
song @ 7:30
album: Stupid Summer Dreams by Botany Bay
song: Nineteen Years Later
He ate too much crabs!
It class D amp am not to keen but like Bluetooth.
The TPA3116 is good for a class D, as far as clean low distortion power goes, as long as it has good complimentary components. Switched my living room setup over after my speaker amp fried all it's transistors one day as a temporary, and was pleasantly surprised.
Niceee
Cool...
Hi bro if you get a chance check out John Audio Tech channel if your interested in amps 🤔 he also has a cute cat 🐈😂