The problem with the SSLs were those pesky VGAs, which produced much more distortion then the NE5534a ever did! That's why Neve used their "Flying Faders" with motorized faders instead of VGAs. The very EARLY Neves were discrete components, but they changed when the NE5534s came out (about 1977).
What do you mean by very early NEVE? Their most appreciate NEVE1081, 1071 and 1073, 1083 are still most sought for...and there's no IC inside them...
Maybe the wrong opamp for this application...?
I made some Comparison Chart:
It would be courteous to acknowledge your source for that plot.
It would be courteous to acknowledge your source for that plot.
Honestly taken from So Just How Quiet is Your Phono Stage?
Hi Mark, not sure what do you mean here? While bias current cancellation schemes will reduce the input bias current, the current noise should be represented correctly in the datasheet. If anything, a lot of these schemes actually worsen the input current noise spec since noise adds as RSS.
Some cancellation schemes have substantial common-mode input current noise that shows up with unbalanced impedances (and RIAA applications are highly unbalanced). LT1028 and LT1115 come to mind. Very noisy in phono MM. I think more modern designs are no longer trying to be clever in this way and are accepting the higher current noise at all times.
Now that ou write it that way, it makes sense. BTW, at least from my experience, the schemes that suffer from common mode current noise are used for reasons outside of current noise, including:
- Ability to trim out the input bias current (usually done in precision and instrumentation amps)
- Headroom requirements.
PS. nice website Stephan
- Ability to trim out the input bias current (usually done in precision and instrumentation amps)
- Headroom requirements.
PS. nice website Stephan
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