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I remember asking a question on here roughly seven months ago for someone to explain what exactly is done in the process of having a Linear Power amplifier modified. Sadly, the answers I received were inconsistent, to say the least, and TODAY my curiosity got the best of me!

One answer I was given is that the OPAMPS are changed.


Myth, busted!

Next, I was told that the Transistors were changed out with Transistors that were more capable:


Uh, NOPE! I could show you the rest, but NOTHING is different!

Finally, I was told that the torrid was re-wrapped, the rail capacitors were changed, and the amplifier was re-biased to take advantage of the different transformer:


Ding, ding, ding.... we have a winner!

Stock rail capacitors are 470uF/50v whereas the modified rail capacitors are 1000uF/63v 85 degree Celsius Xicons. In fact, from what I can tell from the unmodified versus the modified is that ALL capacitors in these amplifiers are of the 85 degree Celsius variety! Sadly, I am NOT going to count the windings on the toroid!

Disclaimer: I only have a basic electronics background and may have missed something. Also, my workbench is a wreck from the 10 or so household projects that I have going on at the moment:blush: Lastly, I hope this was more informative than Geraldo Rivera's opening of Al Capone's vault!
 

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Just to end any confusion, my comparison involves a Stock 1502IQ versus a modified 1502IQ!
 

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this was taken from the LP site

"The power supply fets are changed to parts with double the current capability of the factory devices, the storage capacitors are changed to parts with over double the storage and filtering than the stock components. The transformer's current and voltage capabilities are also increased. The pre-amp and output stages are also refined and improved with various additional parts and part changes to improve the overall sonic capability of the amp. "
 

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...Lastly, I hope this was more informative than Geraldo Rivera's opening of Al Capone's vault!
I was telling a story a while back and made reference to Geraldo Rivera and Al Capone's Vault, and everyone looked at me like I had 3 noses. Thank you for bringing that up, I'm glad someone else remembers it.
 

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Thanks for the great info Mustang. I have no electronic engineering education so I dont know the difference between that old cap and that 85 degree caps.
 

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I was telling a story a while back and made reference to Geraldo Rivera and Al Capone's Vault, and everyone looked at me like I had 3 noses. Thank you for bringing that up, I'm glad someone else remembers it.
That was one of americas most shocking moments. I think it was ranked 10's out of 100. It was also very funny, how people though there was gold, drugs, weaponds of mass destruction (just like Iraq), and then when unlocked.......... ...... .... ...... nothing but dirt.
 

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I bet it is all dependant on which amp is getting modified
Ding, ding, ding. We have a winner. Care to try for the $64 question?:p Mods vary from amp model to amp model and sometimes within the same series (non-i, i, iq). Big differences between the older amps mods and the newer amps mods. Don't ask me what parts, I don't know the specifics, but have seen many done. I do know that rewrapping the torrid is a bitch and must be done correctly or the magic smoke gets released.:laugh:
John
 

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Ding, ding, ding. We have a winner. Care to try for the $64 question?:p Mods vary from amp model to amp model and sometimes within the same series (non-i, i, iq). Big differences between the older amps mods and the newer amps mods. Don't ask me what parts, I don't know the specifics, but have seen many done. I do know that rewrapping the torrid is a bitch and must be done correctly or the magic smoke gets released.:laugh:
John
I know all too well about wrapping a toroid correctly. There is a long funny story involving a physics project that went up in smoke due to an improperly wound toroid which would explain why I don't do toroids, but this run on sentence will have to suffice;)
 

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I know all too well about wrapping a torrid correctly. There is a long funny story involving a physics project that went up in smoke due to an improperly wound torrid which would explain why I don't do torrids, but this run on sentence will have to suffice;)
With no period to boot! :eek:
 

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My modded 3.2s have re-wound torroids. Power at 4 ohms stereo went up quite a bit.

As far as opamps in the 2.2s, I had 2 that had OP-275s and one that had BB2134s from the factory. The one with the 2134s was some of the last made. All of my 3.2s and 4.1s have TL072s in them. One of the 3.2s I have was from the last production run of the amps and they never changed the opamps over the years in them.

I don't this expose of a post is worth more than a grain of salt it should be taken with. And borderlines bad/misinformation.
 
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