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Old Dec 08, 2012, 02:34 AM
jcabetas is offline
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Quote:
Originally Posted by flyn View Post
You might have to explain a few things, log pots & voltage dividers, thanks man.
When you increase the power of an amplifier 10 times, you perceive it as a double loud sound, making the ear response not linear. To make things easier for sound aplications, there are pots in wich the resistance is logarithmic distributed. You can live with an ordinary pot, but adjustments are more dificult to do.

The ouput of any amplifier or mic is equivalent to a voltage in series with the output impedance. To get a lower voltage level you can put two other resistances in series, connected from the voltage source to ground. The voltage trough the resistance R2 connected to ground is:
Vdivider=Vinput*R2/(Routimpedance+R1+R2)

It is usual to use resistances such that the sum are more or less equal to the output impedance. Then you have to choose R1 and R2 to get the factor you are looking for... Or just use a pot.

Sorry, you ask for an explanation
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