THAT2252 RMS Detector Replacement Using A THAT300 Array

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mediatechnology
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Re: THAT2252 RMS Detector Replacement Using A THAT300 Array

Post by mediatechnology »

A picture is worth a thousand words...

For future reference I found this linear domain versus log domain filter comparison in Fred Floru's AES paper.

Image
Linear vs. log-domain filter

The diodes in the final stage of the RMS detector Q3/4 in my drawing or D3 in the above look like rectifiers or peak detectors at first glance to some but they're not.
D3, with it's exponential response, is the log-domain "analog" (pun intended) of a resistor.
D4/OA2 level-shifts.
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