More about LDR attenuators

Hope this design can be useful to someone.

It's an analog "quasi constant" input impedance attenuator, with adjustable output impedance.

This design requires some degree of matching L & R LDRs to avoid unbalances, and lesser matching with control net LDRs (to achieve desired impedances).

With 18 NSL-32SR2 on hand, I've build it (in fact, now it's my favourite volume's att.).
Works pretty well: Not too much unbalance, acceptable attenuation law & impedances.

Using same idea, a "quasi constant" output impedance (volume level independent) can be made.
 

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