Is the first version build entirely without negative feedback as Balanced Line Stage of SOZ, or is small amount of local feedback used, as in Aleph P 1.7?
Sorry for my bad english.
Sorry for my bad english.
By definition, the X topology is a feedback system. If you remove the feedback, it isn't "X" anymore.
Grey
Grey
I would not know, but my guess is that is uses the X-topology which relies on feedback.
Usually you can read up on such things in user manuals from www.passlabs.com
Petter
Usually you can read up on such things in user manuals from www.passlabs.com
Petter
In user manual mr. Pass writes: "The first version used diferential Mosfet circuits operated without feedback." But I am unsure, if it means entirely without feedback or only without global feedback as in AlephP 1.7.
When I say "without feedback" I generally mean
no feedback loop, just degeneration if that.
When I say "no global feedback" I mean no loop from
input to output, although there might be local loops.
no feedback loop, just degeneration if that.
When I say "no global feedback" I mean no loop from
input to output, although there might be local loops.
Apologies...I tend to think of X and "Super Symmetry" as synonyms, and since X is easier to type (I was born lazy, then had a relapse), I tend to use the one letter when possible.
Silly me.
Grey
Silly me.
Grey
Grey that's why it was shortened to Su-Sy 😀
Su-Sy is not a destructive form of feedback and should not be viewed in the same light as negative feedback.
Su-Sy is not a destructive form of feedback and should not be viewed in the same light as negative feedback.
By my reckoning, the letter X only requires one keystroke, whereas Su-Sy takes five.
Ma pore widdle fingers can't take all tha' extra poundin'...
Grey
(Still doesn't excuse me for being mentally sloppy. Seems I'm missing a lot of details this week. I'll try to get some sleep and be back on track tomorrow...or the next day...or the next...)
Ma pore widdle fingers can't take all tha' extra poundin'...
Grey
(Still doesn't excuse me for being mentally sloppy. Seems I'm missing a lot of details this week. I'll try to get some sleep and be back on track tomorrow...or the next day...or the next...)
Good and bad feedback
There is no such thing as good and bad feedback.
The X-circuits in the big power amps (which only licensees of Nelson Pass can use provided patent holds and no workaround can be found) employ local feedback to around a single voltage gain stage. This is very similar to basic op-amp theory (but most op-amps have multiple internal stages, and feedback around these have become universally detested in audio).
Feedback is a method to reduce noise etc. Degeneration is generally considered the "least harmful". The next level, I will call feedback around single loop for lack of a better name, and this is the method used in the X-series power amps.
Feedback free amplifiers are like Yeti's -- many have seen them, but nobody can produce one.
Petter
There is no such thing as good and bad feedback.
The X-circuits in the big power amps (which only licensees of Nelson Pass can use provided patent holds and no workaround can be found) employ local feedback to around a single voltage gain stage. This is very similar to basic op-amp theory (but most op-amps have multiple internal stages, and feedback around these have become universally detested in audio).
Feedback is a method to reduce noise etc. Degeneration is generally considered the "least harmful". The next level, I will call feedback around single loop for lack of a better name, and this is the method used in the X-series power amps.
Feedback free amplifiers are like Yeti's -- many have seen them, but nobody can produce one.
Petter
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