Tibo PA150 Power Amp…..very much a truly nice budget surprise!

[Absolute Concept]

 

[Absolute Concept]

here is the main board

 

[audio_tony]

here is the main board

If there's no driver chip on the underside of that main PCB I'm not exactly sure where the class D drive is coming from in this amp.

In any case, looking at that preamp board suggests that an excessive voltage has been applied to the inputs as there no other evidence of damage elsewhere.

I suspect if you replace that burnt 5532 the faulty channel will work.

BD3 (main board) is a bridge rectifier that appears to be missing - however it's almost certainly soldered on the underside of that main board.

I remain convinced that the class D driver chip must be on the underside of that main board as well.

 

[Absolute Concept]

The aluminum heatsink is glued to the case, if it had been fixed only with screws I would have opened it and taken pictures there too.
Anyway, I tried to replace that NE 5532 first and I'll see after that.
I noticed at the RCA connector on the back of the box that it is widened and when a male RCA is put in it does not seem to stay firmly in contact.
It is possible that the problem arises from there, possibly another cause is changing the RCA cables while the amplifier is on.

Please tell me how to measure the voltage, with the integrated circuit mounted there is no risk of causing a bigger problem,
or do I measure on the pad after removing it from the PCB.

 

[audio_tony]

Those 5532s are surface mount chips - you'll need to take some care when removing them, especially if you are inexperienced.

And yes - you can measure the voltage on the pads with the chip out.

But just be careful when removing the chip that you don't lift the tracks / pads.

What I've done in the past, is take a very sharp pair of side cutters and carefully cut each pin where it joins the body of the IC - then it's just a case of desoldering each leg one by one.

Also use plenty of flux, and don't let the iron get too hot.

 

[Absolute Concept]

thank you for the hint

 

[Absolute Concept]

I replaced the integrated circuit and now the right channel works, but every 15-20 minutes, I hear some kind of sharp impulses in the speaker on the right channel, they appear even when the music is on STOP.From now on, I don't know what to do.

 

[audio_tony]

I replaced the integrated circuit and now the right channel works, but every 15-20 minutes,

Unplug the right channel input from the opamp (input) board (see my highlighted plug below) - LO = "left out" / RO = "Right out". Leave the amp switched on with no signal - if it still pops then you know the problem is on the main amp board.

If the popping stops, then you know the problem is on the input board.

It would be a good idea to stick a 100 ohm resistor in the end of the cable you unplug, just to terminate the input to the board.

So - unplug "J2" - insert a 100** ohm resistor in the end of that lead (you can just push the resistor into the holes where the pins would go.

**any resistor 75 ohms to 270 ohms should be fine.

NOTE: ensure the resistor doesn't come into contact with anything!! Once it's inserted into the end of the plug wrap some tape around it to insulate it.

Switch on the amp, and see if it still pops (no need to play any music).

 

[Absolute Concept]

Thanks, I'll try this option too. I'll get back with info.
This amplifier has a permanent stand by mode, when it sees a signal at the input it starts.
Yesterday I tried with a direct signal on the amplifier board and it didn't start.
That would mean that the signal detection is on the small input board. I should see how I can bypass this.

 

[Absolute Concept]

My files - UploadNow.io

uploadnow.io

 

[audio_tony]

My files - UploadNow.io

uploadnow.io

Are you trying to share something? I'm just prompted to sign up and login (which I don't want to do).

 

[Absolute Concept]

I did as you told me, I removed the right signal cable and put a resistor in and it still made that sound.
After that I removed the left cable and put a resistor in here too and it made it again, so with both signal cables removed from the preamp it still does.
This weekend I plan to take the big amplifier board down, on this occasion we'll also see what's on the back.
Now the only options are to replace all the capacitors, especially the ones near the power resistors which get hot and the high temperature can affect the capacitors.
An interesting thing is that the aluminum radiator is cold, on the other hand the two coils near the transistors you can barely touch, they are very hot.
If I keep taking it apart I could also replace all the transistors.I don't know how the preamp board communicates with the amp board because when it was in standby, to turn it ON, I had to touch the input connectors with an RCA cable and it turned on, the LED turned blue indicating the amplifier's ON status.

Above I have posted a video with the sound that I managed to catch, please try to watch the clip with sound.
Thank you

 

[Absolute Concept]

power resistor and capacitor

 

[audio_tony]

Neither of these two brown caps look good, especially the top one - it appears to have split.

It seems that the amp might be oscillating at the wrong frequency - however I'm not an expert with class d.

I don't think the coils should get hot either.

 

[Absolute Concept]

I have a video file and I don't know where to send it.

 

[Absolute Concept]

The capacitor is not cracked, it is a glue that is applied all over the board, it is something rubbery, silicone

 

[Absolute Concept]

VID_20260416_203947790

www.veed.io

 

[audio_tony]

VID_20260416_203947790

www.veed.io

 

[Absolute Concept]

VID_20260416_203947790

www.veed.io

 

[Absolute Concept]

VID_20260416_203947790

www.veed.io