Someone told me that years ago they build a discrete 741 circuit and it sounded way better than the IC 😛
Isn't that what was done? (With quite successful results?)
https://www.edn.com/national-semiconductor-audio-sound-room/
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Not at all. There is no evidence from that article that the designers of those chips used their ears during the design and implementation phase. That would be silly.
It would be silly for a designer of audio products to listen to the their designs with their ears as they iterate and improve them over the years from the era of the philbrick op amp to the LM4562? 🙄
That is silly subjectivist speculation. No designer worth his or her salt thinks it's good practice to design audio electronics by ear. That would be risible.
I am finding the posts above interesting as well as the whole thread so for the past hour I have spent checking up on historical fact which is quite interesting .
David Fullagar a British electronics design engineer working at Transitron was offered a job at Fairchild after an interview in London as he was offered more than twice his salary he took the job in 1966.
Originally he thought to "uprate " the 709 but changed his mind and designed the 741 , in June 1968
Fairchild ( very good marketing ) announced ="we have a winner " .
At no time was the subjective "sound " of the 741 mentioned and my own memory of those days recalls that this wasn't brought up only the technical specifications .
Yes times change but being honest and reading lots of UK magazines of the 50,s /60,s it was all about spec.
This prevailed into the 70,s but later things changed.
Again --for the record a small company called Elliot Automation Microelectronics at the same time launched a chip with better spec than the 741 but couldn't hope to compete with the excellent marketing guys at Fairchild who were in a different universe from them.
David Fullagar a British electronics design engineer working at Transitron was offered a job at Fairchild after an interview in London as he was offered more than twice his salary he took the job in 1966.
Originally he thought to "uprate " the 709 but changed his mind and designed the 741 , in June 1968
Fairchild ( very good marketing ) announced ="we have a winner " .
At no time was the subjective "sound " of the 741 mentioned and my own memory of those days recalls that this wasn't brought up only the technical specifications .
Yes times change but being honest and reading lots of UK magazines of the 50,s /60,s it was all about spec.
This prevailed into the 70,s but later things changed.
Again --for the record a small company called Elliot Automation Microelectronics at the same time launched a chip with better spec than the 741 but couldn't hope to compete with the excellent marketing guys at Fairchild who were in a different universe from them.
I can't imagine a serious audio designer who does not listen to the design as well as using all the best theory, simulation and measurements that they have available.
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If they were using the best theory, simulations and measurement tools available it would be redundant to conduct a listening test after the fact. Not too mention that the op-amp would be designed with a product specification.
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And if Bob Pease said the DAC design with the metal cans sounds better (after a double blind test at National's Sound Room) you would say nonsense and point out that the plastic and metal package op-amps have the same product specification?
Just like them, you don't know your own folly and ignorance either. How could anybody?
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After all we can not forget that all the finest musical instruments are made under the strictest admonition that the craftsmen must never use their ears and can only craft, tune and evaluate the instrument by FFT and Audio Precision alone. 
The same with all music
The same with all music
"Bob chose the metal cans over the dips every time we did the test! (We did it twice as I recall.)"
"Bob thought the metal can unit "Just Sounded Better"
"But sadly we never got the chance to check out any of these possibilities together."
One persons anecdotal opinion is hardly what you would call conclusive proof or evidence.
I don't consider "Bob Pease" as being equivalent to just any old "One Person" when the subject is op-amps being used for audio.
There are also plenty of designs over the years which needed metal cans, cavity packages or at least die coat to prevent performance degradation due to the over-mold (of the cheapest packaging option: molded plastic).
I think it also says quite a bit that the money and time was spent setting up that sound room along with the switches for double blind testing. Obviously more than one person at a very competent audio design group agreed and signed off on that project and the expenses related to it.
I wonder if Audioman54 can shed anymore light on the role of listening and the audio room at National Semiconductor. But his last activity was December unfortunately.
There are also plenty of designs over the years which needed metal cans, cavity packages or at least die coat to prevent performance degradation due to the over-mold (of the cheapest packaging option: molded plastic).
I think it also says quite a bit that the money and time was spent setting up that sound room along with the switches for double blind testing. Obviously more than one person at a very competent audio design group agreed and signed off on that project and the expenses related to it.
I wonder if Audioman54 can shed anymore light on the role of listening and the audio room at National Semiconductor. But his last activity was December unfortunately.
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After all we can not forget that all the finest musical instruments are made under the strictest admonition that the craftsmen must never use their ears and can only craft, tune and evaluate the instrument by FFT and Audio Precision alone.
The same with all music
There is the crux of the problem: the silly idea that audio amplifiers are musical instruments. 🙄