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OK audio gurus: What are the highly regarded FET-input op amps these days?
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David Hess:

--- Quote from: Marco on December 12, 2018, 12:44:52 am ---
--- Quote from: David Hess on December 11, 2018, 09:09:59 pm ---The OP627 has lower distortion, lower noise, and higher common mode rejection then the jelly bean parts it can replace.
--- End quote ---

Do you think there is anyone in the world who could even hear the difference compared to an OPA140 in an A/B test for a realistic circuit? (ie. not the silly AES one.) Let alone a quality test.
--- End quote ---

In the right application, sure it will be audible.  The OP627 will support a higher closed loop gain at the same distortion level as the TL071/TL081; raise the closed loop gain high enough and there will be an audible difference.  In high sensitivity applications, the difference in input noise will be audible.  The OP627 also maintains lower distortion with lower impedance loads but this should be solved with better circuit design; do not drive low impedance loads with operational amplifiers when distortion or precision matters.
Marco:
Compared to an OPA140 ...
David Hess:
The OPA140 series should be lower distortion but it is not available in DIP packages.  However I doubt the TI datasheet specifications represent reality; it looks like they used a very low source impedance for the distortion tests which is unrealistic for a JFET part.  The included schematic does not show an input cascode so distortion from non-linear input capacitance is likely but they do not discuss this.  Maybe their JFET capable complementary bipolar process solves this problem but if so, they are not saying.

Build a test circuit and do comparisons yourself.
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