Today i was reconnecting my wires of my logitech z680.
When i tested the audio my right front speaker didnt give any sound.
On another channel the speaker works fine and other speakers are also muted on the right front channel.
Now i don't want to buy another set again and want to know what is wrong and if its easy to fix. I searched around the net and found some topics about channels are sepperated and there are also fuses inside. I dismanteled the sub and found the red cicled parts.
Is there anyone who knows more about it and some tips how to solve this problem?
Why i can only find three fuses when there are 5 channels?
I cant see any difference between the fuses and nothing on the board seems burned or anything.
Now i put everything together and all the other channels work ok. I want my right front back.... 🙁
When i tested the audio my right front speaker didnt give any sound.
On another channel the speaker works fine and other speakers are also muted on the right front channel.
Now i don't want to buy another set again and want to know what is wrong and if its easy to fix. I searched around the net and found some topics about channels are sepperated and there are also fuses inside. I dismanteled the sub and found the red cicled parts.
Is there anyone who knows more about it and some tips how to solve this problem?
Why i can only find three fuses when there are 5 channels?
I cant see any difference between the fuses and nothing on the board seems burned or anything.
Now i put everything together and all the other channels work ok. I want my right front back.... 🙁
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Moved to Chip Amps forum 🙂
Not really my thing but a few pointers.
Fuses... you need to measure them to make sure they are not open circuit. Why only three fuses ? Because the fuses will protect the power rails and they will be common to many parts of the circuitry.
Typical failure of amps like this are the actual output IC's and without seeing a circuit I'd just be guessing. Are they LM3886's or a TDAxxxx of some variety.
Not really my thing but a few pointers.
Fuses... you need to measure them to make sure they are not open circuit. Why only three fuses ? Because the fuses will protect the power rails and they will be common to many parts of the circuitry.
Typical failure of amps like this are the actual output IC's and without seeing a circuit I'd just be guessing. Are they LM3886's or a TDAxxxx of some variety.
Those in a red circle are ferite inductors in signal line,probably for left,right and center chanel.
Check the Tda output's. 🙂
Check the Tda output's. 🙂
I found on the net that the z680 serie is working with TDA7493 amplifiers.
Now i must find out which one of the 7 (?) is the right one and hope someone can fix (solder) it.
When just one channel is lacking this is the biggest chance of failure you mention?
Now i must find out which one of the 7 (?) is the right one and hope someone can fix (solder) it.
When just one channel is lacking this is the biggest chance of failure you mention?
Very good chance it will be a failed TDA. You could try tracing the failed speaker output back to the appropriate IC.
You could do some basic checks first, but be extremely careful because one slip of a meter slip would be disastrous. Measuring supply voltages at the IC's is a first step.
Here is the data sheet for the TDA7293. (The TDA7493 ??? is only a 3 watt Class D amp)
I opened the case again and looked through the wires and the TDA's
There are seven (TDA7293) of them but i asume the sub might use two?
I found out the right front channel must be u7 and i put some pictures of the TDA below. I cant find any differences with the other TDA's and no burned places or damages on the board itself. Where to look now? There is a controller unit with the z680. could it be in there? I also tried different inputs so i cant be the coax input going into the controller.
And when i want to measure the TDA itself i have no clue where to start.
Here are the images of the right front TDA:
There are seven (TDA7293) of them but i asume the sub might use two?
I found out the right front channel must be u7 and i put some pictures of the TDA below. I cant find any differences with the other TDA's and no burned places or damages on the board itself. Where to look now? There is a controller unit with the z680. could it be in there? I also tried different inputs so i cant be the coax input going into the controller.
And when i want to measure the TDA itself i have no clue where to start.
Here are the images of the right front TDA:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Testing follows basic steps. If the supplies are all OK then you really need to look with a scope and trace the audio.
There are other ways and means but I suspect you might lack the practical experience to do this successfully... with no scope and no test equipment you could "buzz" each input to each of the TDA's to see if you get any response. One might be dead. But you need to be very very careful. One slip and it all goes pop and probably taking the speakers with it too.
There are other ways and means but I suspect you might lack the practical experience to do this successfully... with no scope and no test equipment you could "buzz" each input to each of the TDA's to see if you get any response. One might be dead. But you need to be very very careful. One slip and it all goes pop and probably taking the speakers with it too.
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