TPA3116D2 Amp

Hello TPA3116D2 interested


I purchased 2.1ch board which marked XH-M139. This board has many design issues. So I did some modification on my board. Modification details are shown in machine translated following URL.
park8.wakwak.com/~hilo/audio/tpa3116d2_amp3ch/index.html - Translator


I did as follows...
- Add power on/off pop mute drive circuit
- Add 12dB/oct HPF for stereo channel
- Change bad mono-mix circuit design
- Change TPA3116D2 switching frequency 400kHz to 1.2MHz
- Fix the synchronous clock signal waveform shape issue
- Change magnetically saturated toroidal inductors

Schematic circuit diagram is available, but it's not perfect may be...

HILO

Thank you so much Mr. HILO for the Schematic Diagram and the correction modification.:up:

especially the circuit diagram, so useful to locate components and do modification. :)
 
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@FauxFrench - thanks for the reply.
if removing the 100k resistors is the solution - I need you help please to understand which one I need to remove, since near every one out of four TPA3116 chip I got TWO 100k resistors ( and near 1 of them THREE 100k ).
can you please point the right one by marking on the image I uploaded ?
please enlarge to see all small details ( bottom left side button on image )
(top - all board )
4fICG3S.jpg


To continue my story, I noticed that a similar board that's sold on aliexpress got extra two 1uF (near the master vol pot ) - that don't exist on my board.

also on that aliexpress board, the 3rd & 4th coil in the coil's row ( counting from the DC input side ) is a blue (electrolytic?) coil and not copper looped coil like the rest of the coils in that row - and in my own board I got regular coil like the rest of the row.

Might either of this be the source of the hiss/ground-floor anoying noise ?
Should I add these extra two 1uF caps near the master vol pot ?

Update:
ok, crap I saw another seller on aliexpress that sell the same complete amplifier ( like mine ) BUT this board got these extra two 1uF caps near the master vol.
 
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I have the same question. I remembered somewhere that 3116/3118 SNR will degrade a little bit if switching at highest frequency (1.2M) since the switching period becomes too short, the PWM module may not be able to control the duty cycle well enough.

I doubt it. 1.2M decreases the overall switching noise by putting it high enough that the inductors would do better work of filtering the output and it's more efficient at 1.2M...

All of that would work if the inductors can handle 1.2MHz properly.
 
I doubt it. 1.2M decreases the overall switching noise by putting it high enough that the inductors would do better work of filtering the output and it's more efficient at 1.2M...

All of that would work if the inductors can handle 1.2MHz properly.

I am not talking about switching noise. I am worried about pushing the PWM modulator to the limit. Anyway, the degradation will be minuscule.
 
Hello,
What is the advantage of change the switching frequency from 400kHz to 1.2MHz?

Thanks


Hi, eX Radikal-San and gandolf-San


The most big advantage is reducing the heat of inductors (but, depend on parts useable frequency limit). I checked PWM switching waveform, rise/fall time was fast enough for 1.2MHz toggle. Additional thing is some characteristic of high frequency range sound will change, such as ride cymbal or Hi-Hat. I felt 1.2MHz sound is more natural and smooth than 400kHz. That's why I decided to change the switching frequency.


HILO
 
Has anyone listened to the Knacro 2.1 board? I recently purchased one after reading such great reviews of the TPA3116 amps and since it was a perfect solution to a project I was working on.

Soon after it arrived I hooked it up to a full set of speakers that I have grown to know and love with many other amplifiers. The speakers are a pair of TC9FD full-range drivers for L&R and for the sub channel, my personal ‘standard’, ported 8” passive sub. Power for the board was a freshly charged Milwaukee 18V lithium drill battery, which rests at 20.4 VDC.

Upon listening to it, I was quickly appalled by the sound. The grainy upper midrange was so fatiguing. No amount of fiddling with the Treble knob helped. I’ve tried searching for any mods for this board, but to no avail.

At this point, I am not sure if it is the preamp processing that is the issue or the surface mount 15mh inductors on the output side.

Anyone have a similar experience?
 
I do not know the "Knarco" board. I have several other TPA3116/18 boards.

A forum member, a few months back, described how he was disappointed with the mid-range of his TPA3116 amplifier used with his (analytic) full-range drivers in a horn construction. Shortage of details if I remember well.
TPA3116 is great value for money, as this member also agreed. A stereo amplifier costs in the range 5-20$. The chip is designed for a typical use in sound-bars and the like. For a sound-bar, it is great and for many other ordinary applications as well. And, ideal for DIY beginners. It is not top-of-the-range when you really test it for nuances in the mid-range with analytic speakers. It has to be seen in the light of the very modest price.
 
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Re: Knacro TPA3116 Board

My experience is TPA3116 generates a lot of hiss if it looks into a high impedance (>10K) at the input. iIt may be an impedance that is only high impedance at higher frequencies, like a poor ESR capacitor.

I always try to put 4K7 across (to ground) the input terminals if the source allows that.

Has anyone listened to the Knacro 2.1 board? I recently purchased one after reading such great reviews of the TPA3116 amps and since it was a perfect solution to a project I was working on.

Soon after it arrived I hooked it up to a full set of speakers that I have grown to know and love with many other amplifiers. The speakers are a pair of TC9FD full-range drivers for L&R and for the sub channel, my personal ‘standard’, ported 8” passive sub. Power for the board was a freshly charged Milwaukee 18V lithium drill battery, which rests at 20.4 VDC.

Upon listening to it, I was quickly appalled by the sound. The grainy upper midrange was so fatiguing. No amount of fiddling with the Treble knob helped. I’ve tried searching for any mods for this board, but to no avail.

At this point, I am not sure if it is the preamp processing that is the issue or the surface mount 15mh inductors on the output side.

Anyone have a similar experience?


Hi sskloss-San, FauxFrench-San,


I had same kind of feeling something like this TPA3116D2 board.

IMG_1625.jpg
The signal input part audio coupling MLCC capacitor changes sound characteristics a lot. So I changed them to ordinary Electric Caps. (I believe Film caps will be the best choice for this part). As a result of this, the sound was changed to plain normal. But I met a big power ON/OFF Pops Noise:(, so I had to attached a muting driver circuit like this...
MuteDriver.gif
(Diver Circuit's output drives pin12 of TPA3116D2)
I guess inductors on Knacro board are fair for typical use)

HILO
 
The 3116 is power-pad up. Beside this I have bare PCBs for 3118/3128, with all 0402 and up component size. Needs reflow equipment to stuff and solder.

@gandolf, performance degradation is more than minuscule if the layout isn't made for that high frequency. I have meaurements made in the past if this is from interest.

Oh right I was thinking of TPA6120.. my bad. Still, wouldn't be an easy one to solder :eek:

I do not know the "Knarco" board. I have several other TPA3116/18 boards.

A forum member, a few months back, described how he was disappointed with the mid-range of his TPA3116 amplifier used with his (analytic) full-range drivers in a horn construction. Shortage of details if I remember well.
TPA3116 is great value for money, as this member also agreed. A stereo amplifier costs in the range 5-20$. The chip is designed for a typical use in sound-bars and the like. For a sound-bar, it is great and for many other ordinary applications as well. And, ideal for DIY beginners. It is not top-of-the-range when you really test it for nuances in the mid-range with analytic speakers. It has to be seen in the light of the very modest price.
There are factors that contribute to poor sound, quite a lot of TPA3116 boards float around with AWFUL input caps and cheap part choices, one of the biggest telling is when you see SMD inductors being used. NO JUST NO.

Usually the SMD inductors are not the real stuff but rather just a badly made ultra cheap version.
 
FauxFrench – Come to find out the board I have is not from KNACRO, as was advertised on Amazon. After a lot of searching, I still have no idea who the manufacturer is. The board I received isn’t even the same as pictured on Amazon either. Below is a pic of the one I have mounted in a case my brother printed up.

Please keep in mind that I am old school and this is my first chip-amp. That said, I REALLY want to believe that what I claim as lack luster sound is due to all of the preamp processing and use of sub-par parts.

On one hand, for the $35.99 I spent on it, the board is pretty amazing for what it is – a powerful, palm sized 3ch amp with a built in x-over and an array of controllability that is essentially plug-and-play. On the other hand, all of that controllability is nothing if I cannot listen to it long term. I don’t claim to have golden ears, but you cannot deny something that is uncomfortable to listen to.

To that end, I am currently looking for a good quality, 2 channel TPA3116 board (with through-hole parts if possible) to see what they really sound like and what a little modding can do. Can you suggest one or a few to put on my short-list? I’ve been building/modding audio gear for 30 years and would like to have something worth tinkering with.

BTW, my full range drivers are not necessarily ‘analytic’, but they do make a good source/amp sound good and a bad source/amp sound bad. If you don’t own a set or haven’t spent much time with some decent full range speakers, I highly suggest spending the $40 or so for a pair of drivers and knock-down cabinets. They are not end-all/beat-all, but they do have a sound that is so pleasing in their own right that any audio fan should have a pair in their inventory.
 

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FauxFrench – Come to find out the board I have is not from KNACRO, as was advertised on Amazon. After a lot of searching, I still have no idea who the manufacturer is. The board I received isn’t even the same as pictured on Amazon either. Below is a pic of the one I have mounted in a case my brother printed up.

Please keep in mind that I am old school and this is my first chip-amp. That said, I REALLY want to believe that what I claim as lack luster sound is due to all of the preamp processing and use of sub-par parts.

On one hand, for the $35.99 I spent on it, the board is pretty amazing for what it is – a powerful, palm sized 3ch amp with a built in x-over and an array of controllability that is essentially plug-and-play. On the other hand, all of that controllability is nothing if I cannot listen to it long term. I don’t claim to have golden ears, but you cannot deny something that is uncomfortable to listen to.

To that end, I am currently looking for a good quality, 2 channel TPA3116 board (with through-hole parts if possible) to see what they really sound like and what a little modding can do. Can you suggest one or a few to put on my short-list? I’ve been building/modding audio gear for 30 years and would like to have something worth tinkering with.

BTW, my full range drivers are not necessarily ‘analytic’, but they do make a good source/amp sound good and a bad source/amp sound bad. If you don’t own a set or haven’t spent much time with some decent full range speakers, I highly suggest spending the $40 or so for a pair of drivers and knock-down cabinets. They are not end-all/beat-all, but they do have a sound that is so pleasing in their own right that any audio fan should have a pair in their inventory.

Found your board with three different trading names:

TPA3116 Bluetooth Amplifier TPA3116D2 2.1 Subwoofer Amplifier Digital Audio Board 50+50W+100W Bass HIFI For Subwoofer Speaker-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group

Aiyima 2017 New TPA3116 Subwoofer Amplifier Board 2.1 Channel High Power Bluetooth Audio Amplifier Board DC12V 24V 2*50W+100W-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group

Bluetooth 4.2 TPA3116 2.1 Channel Digital Audio Amplifier Board Modules Subwoofer Speaker Amplifiers DC12V 24V 2*50W+100W -in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group

You are right, it may be the pre-amp circuit that limits the performance. I do not have that particular board and cannot say precisely how "awful" it sounds. My comment about the limited quality of the TPA3116 is meant to say: "TPA3116 boards are really cheap for what you get, just don't expect the board to be the best sound you have ever heard". A very rough and subjective statement is that theTPA3116 performs like a 2x30-40W commercial amplifier. Impressive for the moderate price but not a reference in sound.

If you want to know the performance of the TPA3116 chip, you are right in looking for a simple TPA3116 amplifier without anything "extra". See my next posting.
 
After some searching, I found a perfect candidate...

DIY Electronics KAA10021 Kit

I haven't found any reviews, build or modding articles on this kit, but it seems to follow the TI spec well enough. I have the upgrade parts necessary for the signal path on hand already, so it should be what I am looking for.

Fingers crossed that it's not another $35 that will sit on a shelf.


Most TPA3116 implementations are focusing on the price because the TPA3116 chip itself is very price-competitive. Low price means automated assembly with SMD components.
A good TPA3116 implementation should have:
* pretty large output filter chokes, preferably of the toroidal type,
* foil output filter capacitors,
* foil input coupling capacitors,
* good size power line decoupling capacitors onboard,
* decent size heatsink,
* over-sized connection terminals for power and speakers.
 
I got this red/orange Sanwu one recently: TPA3116 50W*2 digital amplifier board PBTL 100W mono power amplifier
Pretty cheap on Ebay: DC 12V-24V TPA3116 Mono 100W Digital Audio Power Amplifier Board BTL Out Amp | eBay

It has SMD output filters, but the rest of it fits in with FauxFrench's list. Under the big heatsink there are SMD ceramic bootstrap caps, and circuitry that looks like it could be doing a start-up mute. It has less of a crack than the YJ blue/black one I bought before. I prefer this Sanwu one, it's a neater little board and can easily be made mono PBTL with the addition of a few well-marked solder links underneath. The only disadvantage is the gain resistors are SMD. Mine came with 39k and 100k so I removed the 100k to get 20dB. That fits in nicely with the 1uF input caps.

On both the YJ and this Sanwu I got a lot of hiss from my M-Audio Delta 192 soundcard. Going to 20db gain reduced it but it was still too obvious. I'm using an NE5532 based headphone amplifier as a preamp for now and that got rid of the hiss. No hiss from an mp3 player either. I'm guessing it's an impedance mismatch.

Once the hiss is overcome they are fantastic little amps. Tiny and clean. I'm using a Toshiba 15V 5A laptop brick.
 

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Hi, eX Radikal-San and gandolf-San


The most big advantage is reducing the heat of inductors (but, depend on parts useable frequency limit). I checked PWM switching waveform, rise/fall time was fast enough for 1.2MHz toggle. Additional thing is some characteristic of high frequency range sound will change, such as ride cymbal or Hi-Hat. I felt 1.2MHz sound is more natural and smooth than 400kHz. That's why I decided to change the switching frequency.


HILO

Hi, CyberPit, this is just for your information, not saying you have to change anything.

The problem with pushing PWM switching frequency is about the resolution of the PWM modulator's output (duty cycle), not the rising/failing slew rate. To achieve the rated 102dB SNR, the resolution or linearity of the PWM modular has to be better than ~17bits, which means when input signal changes 0.00076%, the duty cycle needs to change 0.00076%. If you switch at 400KHz, the time resolution is 19ps and if you switch at 1.2MHz, it shrinks to ~6.6ps. To achieve latter it is very difficult, especially considering high voltage process usually are slow (have some experience with TSMC 180nm BCD process but TI has its own process optimized for power application. After all, Class D is just a fancy buck converter). To make it worse, I think all these Class D amps are using internal RC osc as the CLK generator (thus these 10% switching frequency error for each settings.). RC oscillators are not good at jitter, several ps is common. For the same amount of jitter, the duty cycle distortion becomes 3X worst simply because you push the PWM resolution requirement 3X higher, by switching it by 1.2MHz. Lastly, please note that all the parameters from datasheet are designed and related at default setting. The other switching frequencies are only intended for AM avoidance.

Anyway, what is the most important is your own experience so if you like the sound with 1.2MHz switching frequency, go for it and enjoy the music.