Studio Reference Amplifier

sr200 studio refer.

There is no evidence how their units behave, maybe it all peaks like yours? Just for curiosity, it is good to know how to get rid of it.
I agree .That is the reason i spent more time testing again and again.
However It is very good news that someone say ''all is ok in my unit.''
In this way we are sure that nothing is wrong in prototype so it's my problem.
 
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What did you say about this???

My SR200 is working perfectly after inclusion of the missing caps. My issue before is like what you are experiencing now if I remembered correctly I have smoking zobel and blown OP's.

I don't have a scope so I cannot check for any oscillations present in my amp now but it's a working amp and I don't have any problem with it, no smoking no burned components and it's singing pleasantly into my ears :). Surely you will find what is troubling you.

Actually I printed the schematics and the PCB layout you choose, I'm checking it right now but I cannot find any errors...check for resistors wrong value, PCB tracks short circuit (I reckon the signal track width which might picking up signal from the power line).
 
I forgot to mention that I removed the RC network from the Main PCB, I solder it in speaker terminal.
Me also
 

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My SR200 is working perfectly after inclusion of the missing caps. My issue before is like what you are experiencing now if I remembered correctly I have smoking zobel and blown OP's.

I don't have a scope so I cannot check for any oscillations present in my amp now but it's a working amp and I don't have any problem with it, no smoking no burned components and it's singing pleasantly into my ears :). Surely you will find what is troubling you.

Actually I printed the schematics and the PCB layout you choose, I'm checking it right now but I cannot find any errors...check for resistors wrong value, PCB tracks short circuit (I reckon the signal track width which might picking up signal from the power line).
Dr friend .
Μy unit is also stable under routine operating conditions without overheating and adverse events.
The problem occurs only under control conditions and only, as many times highlight , at square wave signal.
I have check everything again and again
In any case appreciate your effort to help me.
Many many thanks to all
 
sr200 studio refer.

Post a pic of both the input signal and the output signal.

If you feed in an input signal that is slightly too fast, or with slight overshoot, you usually find that an amplifier will output an exaggerated overshoot.

Your massive overshoot could be due to bad input signal.
Hi dear Adrew.

There's something not like to me in this case.
This is one reason that I tried with another generator and other oscilloscope.
Today I decided to change the supply of the organs leaving the generator on the isolation transformer while oscilloscope directly from the network.
This mode will not share a common ground.
you have note that with the same procedure I have checked too many amplifiers without ever Troubleshooting
 
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You added 10pF compensation and peaks are still there. Something behind is slow. Try remove c10/11 and increase added capacitor value (22p, 47p...). But be careful in view of oscillations.

C10/11 can be removed and add 100pF like on this circuit, R31/32 value can be decreased.
 

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Dr friend .
Μy unit is also stable under routine operating conditions without overheating and adverse events.
The problem occurs only under control conditions and only, as many times highlight , at square wave signal.
I have check everything again and again
In any case appreciate your effort to help me.
Many many thanks to all

Ok now I fully understand, sorry about that.

I will check if I can borrow a scope from a friend I will check if the overshot is present also in my amp, will post a finding here too.
 
sr200 studio refer.

Hi dear Adrew.

There's something not like to me in this case.
This is one reason that I tried with another generator and other oscilloscope.
Today I decided to change the supply of the organs leaving the generator on the isolation transformer while oscilloscope directly from the network.
This mode will not share a common ground.
you have note that with the same procedure I have checked too many amplifiers without ever Troubleshooting

Good news friends!:):):)
As previously stated, today made ​​the above instrumentation wiring.
The overshoot decreased to half immediately!
Then added a 4p7 parallel to 10pf ..beter results
The final choice is18pf.
Take a look.
1)1KHz
2)10KHz
3)20KHz
4)30KHz
5)40KHz
 

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sr200 studio refer.

in continuity with previous some other pictures.
The down oscilloscope show the input signal
The up oscilloscope show the output of amplifier
 

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Apex sr 200 studio referance.

All the truth about Apex sr 200 studio reference in photos.
 

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Apex sr 200 studio referance.

continue
 

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