lagoausente
Well-known member
Hello everybody. Hope someone can give me a light,
Some time ago I built the Supergreen pre. Some months ago I changed the case to put it in a rack unit with headphones amp etc. Have replaced the output opamps NE5534 by the LME49710, what are the single version of the LM4562na.
I tried it yesterday, and have found that some of the fron opamps NE5532 I had around was wrong. One not working, other has a lot of noise. Replaced with a new one and worked ok in both channels (have two).
Well, I wanted to try the LM4562na I ordered sometime ago. It didn´t work, no sound, and the opamp got very hot, and finally fried. I blown four of this opamps on my trying, no one work. Finally, I tried the last on my Cmoy phones amp, and worked ok, then tried on the Supergreen and fried again.
I remember that some months ago I tried and comprared the opamp I still have alive in my Cmoy and worked perfectly. Now, they are fried. But if I put again the NE5532 it works and this is not fried. ???
Have checked the supply requirements for the LM4562 and it´s 2.5V to 17V, with absolute max rating of 36 volt total. I power the preamp with four 8,4volt batteries, so have +/- 16.8 volt, max 33.7 or so.
Well, I would like to know If it´s posible to protect the opamp to avoid get fried while checking if it works or no, or if I must blown a lot of opamps while I find the problem..
And the other point is, what I should need to check? What can be the problem? What should I check to find out what occurs.
I remember that this type of opamp worked ok some months ago in the same preamp. The only changes I made was the output opamps, and maybe a diferent battery voltage, but still seems in the correct range..
Any ideas?
Attached below the supergreen schem.
Some time ago I built the Supergreen pre. Some months ago I changed the case to put it in a rack unit with headphones amp etc. Have replaced the output opamps NE5534 by the LME49710, what are the single version of the LM4562na.
I tried it yesterday, and have found that some of the fron opamps NE5532 I had around was wrong. One not working, other has a lot of noise. Replaced with a new one and worked ok in both channels (have two).
Well, I wanted to try the LM4562na I ordered sometime ago. It didn´t work, no sound, and the opamp got very hot, and finally fried. I blown four of this opamps on my trying, no one work. Finally, I tried the last on my Cmoy phones amp, and worked ok, then tried on the Supergreen and fried again.
I remember that some months ago I tried and comprared the opamp I still have alive in my Cmoy and worked perfectly. Now, they are fried. But if I put again the NE5532 it works and this is not fried. ???
Have checked the supply requirements for the LM4562 and it´s 2.5V to 17V, with absolute max rating of 36 volt total. I power the preamp with four 8,4volt batteries, so have +/- 16.8 volt, max 33.7 or so.
Well, I would like to know If it´s posible to protect the opamp to avoid get fried while checking if it works or no, or if I must blown a lot of opamps while I find the problem..
And the other point is, what I should need to check? What can be the problem? What should I check to find out what occurs.
I remember that this type of opamp worked ok some months ago in the same preamp. The only changes I made was the output opamps, and maybe a diferent battery voltage, but still seems in the correct range..
Any ideas?
Attached below the supergreen schem.