Velleman K4700


2004-03-28 10:49 am
I am building this speaker protection circuit and just wondered the purpose of R23, R24, R25 and R26 (see attached diagram) and weather i need to include them.

In the instruction manual (see instructions1) it says to include them if:

If the amplifier to which the module is to be connected has a simple power supply (asymmetrical supply) i.e. an amplifier with output elcos, the following resistances has to be mounted...

My amplifier is a non inverting lm3875 with a regulated 18V 0 -18V power supply so i am guessing it doesnt need these resistors since the supply is symmetrical ?

What confuses me is what elcos mean i thought it might mean electrolytic capacitors? but am unsure. Also my amplifier has 2.2uF non polarised capacitors if this makes any difference.

Hope someone can explain :)

Thanks very much


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