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We usually cascade filters in ascending Q-factor to avoid saturation in each individual stage. But are there advantageous situations when we cascade filters by descending Q-factor?

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    \$\begingroup\$ Not that I am aware of. I made the mistake once of getting this wrong and it was a tad embarrassing. \$\endgroup\$ – Andy aka Feb 27 at 17:06
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If there is no risk of saturation you might want a relatively broadband preamplifier before you apply a higher-Q filter. The input-referred noise of a high-Q active filter can be pretty bad.

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  • \$\begingroup\$ aren't you just agreeing with the original statement rather than examining reasons why the reverse might also be applicable in certain situations? \$\endgroup\$ – Andy aka Feb 27 at 18:51
  • \$\begingroup\$ @Andyaka I don't see the word "noise" in the original statement. \$\endgroup\$ – Spehro Pefhany Feb 27 at 18:52

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