TPA3116D2 Amp

[Think]

.................

PSU:
90w 19v 4.7a laptop psu
................
2. that PSU with deliver, 45W at 8 ohms? Ignoring loses, potentially 22.5+22.5 at 8 ohms without the sub, which seems to be plenty for the size of the room and how we listen. However the sub would eat into that, but it is a small sub so probably not a lot?

The power supply is powerful enough: can deliver enough amps.
http://www.ti.com/lit/ds/symlink/tpa3116d2.pdf

@19V The amps can deliver about 2x22W@8ohm + 1x50W@4ohm

There is a switch on the board to select fullrange or high pass filter at about 150hz for the tops; the low pass for the sub is variable; you can adjust it so that is just fills in the lows.

 

[nightmare007]

hiss/noise fix (gain fix?) for TPA3116D2 5.1 system - help needed

Hello,
wonderful thread here - I hope you can help me.
I recently bought this ready out-of-the-box TPA3116D2 5.1 system from aliexpress..

my issue is the "famous" "ground-floor" hiss/noise coming out of the system, w/ & w/o any external input.
all the fixes mentioned in the forum and on youtube, are for 2.1 channel TPA3116D2 systems - not for 5.1 with x4 chips - so I dunno what to do.

I've tear-down the amp box, removed the heat-sinks and made few photos of the board- SEE HERE.

What I noticed is that:

• All my 5 vol potentiometers are of 95k or 85k ohm.
• Near every chip ( 4 of them, I presume TPA3116D2 ) I got x2 100k ohm + x1 39k ohm resistors.

what should I (de)soldier ( potentiometers/resistors ) to remove that awful hiss coming out of the system ?

* should I only replace the vol potentiometers to 10k each or just main vol ( w/o touching the resistors near the chips ) or should I mod both resistors & potentiometers ?
* should I switch between the 100k and 39k resistors or replace them w/ other ohm resistor ?
(also which 100k should I mod since there are couple of them near every chip and near one chip there are x3 of 100k ohm resistors ?)

Hope you can guide me ( and if possible with marking on my images )
Much obliged

P.S - I use 24v 6A power supply on that system.

 

[nightmare007]

What I noticed is that:

• All my 5 vol potentiometers are of 95k or 85k ohm.

My bad - the pots are "B5K", so AFAIK its 5k ohm... so I guess the hiss isn't caused by the pots but the resistors pair(?) of 100k and 39k.
Question is - which 100k should I replace ( there are x2 near every chip ) and also not sure that I just need to switch between 100k<->39k - instead I might need a different resistor all together - but which ?

 

[FauxFrench]

My bad - the pots are "B5K", so AFAIK its 5k ohm... so I guess the hiss isn't caused by the pots but the resistors pair(?) of 100k and 39k.
Question is - which 100k should I replace ( there are x2 near every chip ) and also not sure that I just need to switch between 100k<->39k - instead I might need a different resistor all together - but which ?

I know of two ways to get rid of the very annoying hiss: lower the input impedance and/or reduce the gain.
With a 5KOhm potentiometer, the input impedance is low enough.
The gain, you are already aware of, is changed with the resistor combination. R1=39K/R2=100K is a setting for 32dB gain. By removing R2 (100K) you get the minimum gain of 20dB. According to the datasheet, R1 should then be 5.6K. Replacing an SMD resistor is difficult while only removing one is doable.
I had 47K/75K for 36dB gain and by only removing the 75K I got 20dB gain. So, for a start leave the 39K (R1) in place, it will most likely work like that.

Lastly, the hiss could be caused if the TPA3116 input coupling capacitors are of a poor quality electrolytic type.

 

[nightmare007]

I know of two ways to get rid of the very annoying hiss: lower the input impedance and/or reduce the gain.
With a 5KOhm potentiometer, the input impedance is low enough.
The gain, you are already aware of, is changed with the resistor combination. R1=39K/R2=100K is a setting for 32dB gain. By removing R2 (100K) you get the minimum gain of 20dB. According to the datasheet, R1 should then be 5.6K. Replacing an SMD resistor is difficult while only removing one is doable.
I had 47K/75K for 36dB gain and by only removing the 75K I got 20dB gain. So, for a start leave the 39K (R1) in place, it will most likely work like that.

Lastly, the hiss could be caused if the TPA3116 input coupling capacitors are of a poor quality electrolytic type.

@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 )

( top - left side )

(top - right side )

 

[FauxFrench]

A very relevant question: which 100K to remove?

It is the 100K resistors that are connected between pins 7 and 8 of the IC. I cannot see for sure but I believe it is the ones located between the ICs and the group of electrolytic capacitors (close to the 39K resistors). The 100K resistors are also connected to one terminal of the 39K resistors. Please verify with an Ohm-meter.

I also notice 1uF electrolytic input coupling capacitors that may be the cause of hiss.

 

[Think]

The top left cap in the pictures, front left on the board does not look healthy to me, but that might just be the light.

 

[nightmare007]

I also notice 1uF electrolytic input coupling capacitors that may be the cause of hiss.

OK, I used a wire to bypass the 100k ohm R - nothing is changed - so I can only guess that the "hiss" is not coming due to resistors, i.e high gain ( maybe since I got 5K pots on all 5 vol dials )

so the only logical thing to think of, is as you stated - bad coupling capacitors.
I noticed that near every pot, there a "1U" text on the board for a cap, but what's actually soldier is a 2.2uF (5V) capacitor instead of expected 1uF cap.

so for sure I want to replace these "1U" capacitors.
few Q remains:

1. Should I replace them to a better quality 1uF or 2.2uF (of 5v rating ) ?
2. What are "better quality" capacitors VS current soldier type (electrolytic ) ?

The top left cap in the pictures, front left on the board does not look healthy to me, but that might just be the light.

at the top most photo I posted, above the tow of pots is a red LED which its legs are bend into the front panel of the box.
is that what you meant ?

 

[Think]

No, the upper capacitor (of the 21) in the pictures or far left on the board; isn't it swollen / it's top popping up?

 

[nightmare007]

No, the upper capacitor (of the 21) in the pictures or far left on the board; isn't it swollen / it's top popping up?

nope, it's the same level (at the tops) comparing with the caps near it.
it's the caps of the center speaker.

 

[Dac0908]

So, anyone remembers my hiss problems with dual chip board?

http://www.diyaudio.com/forums/class-d/237086-tpa3116d2-amp-1039.html#post5416186

I haven't touched those yellow capacitors on input yet, or anything on the board actually. Input is still bypassed with little pots on amp board turned up all the way (but I will bridge and remove them when I work out come kind of enclosure), only news is now it is paired with OPA2604 preamp board and this sounds really good to my ears. Can't notice any hiss now, volume control is nice, tone controls too. Nice combo! Sound source is a generic PCM2704 USB DAC so nothing high res, but I'm not complaining

 

[eX Radikal]

R=4x10 ohm, C=4x330 pF

Capacitors are connected to PCB ground plane after scratching the paint in two points.

By the way, a piece of 2.54mm strip contact can be used as input connector (can be seen in first picture)

Hello, how to do this RC snubber? The resistor and cap are connected in series or they are both connected to ground in the middle too?
So, for exemple: JP3-Resistor-Capacitor-Ground or JP3-Resistor-Ground-Capacitor-Ground?
Can I use any kind of capacitor?

Also, can I connect the ground to the GND pin at the left or to a negative leg from PS cap or can't?

Thanks in advance.

 

[msj965]

need help masters

hello
i just bought this amp on eBay but when i hook it up turn the volume 1/2 way the sound on my speaker cracking like cutting off. don't know if the speaker or the amp it self. my yamaha speaker indicates 6ohms. pls help me i attached my amp here.

http://www.diyaudio.com/forums/atta...6d2-amp-screen-shot-2018-01-05-7-27-34-am-jpg

 

[eX Radikal]

Probably low voltage.

 

[francolok]

Probably low voltage.

..or low power of power supply...

 

[rabbitz]

.... and low current. You may want to give the specs of the power supply you are using.

I have that module and works well with a Q Acoustics 2010i that is 6 ohm nominal using a 18V 1.6A SMPS.

 

[CyberPit]

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

 

[CyberPit]

Hi



My HX-M139 (Dual TPA3116D2 2.1ch Board) modification details...
park8.wakwak.com/~hilo/audio/tpa3116d2_amp3ch/index.html - Translator


- Add muting driver circuit
- Change of mono mixing circuit
- Change of TPA3116D2 switching frequency
- Change synchronous clock waveform signal shape
- Change magnetically saturated toroidal inductors


HILO

 

[eX Radikal]

Hello,
What is the advantage of change the switching frequency from 400kHz to 1.2MHz?

Thanks

 

[gandolf]

Hello,
What is the advantage of change the switching frequency from 400kHz to 1.2MHz?

Thanks

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.