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previous: JR. thx liam i was under the i... -- 4/5/2000 6:07 PM

Re: what does the cap actually do?

4/5/2000 6:34 PM
ChrisM	Re: what does the cap actually do? A capacitor is like a resistor that only works for low frequencies. At DC levels, a capacitor is an open circuit, looking like an infinitely large resistor. As the frequency of the signal increses from DC, the resistance(or impedance as they call it when you're dealing with capacitors and inductors) decreases, until the capacitor looks like a short circuit at high freqeuncies. If I'm right, bright caps are wired in parallel with the pot. Impedances in paralllel look most like whatever impedance is smaller, so at high frequencies the capacitor and pot combo look like a very small resistor, and at low freqeuncies the cap and pot look like just the pot. So, in short, the capacitor is allowing the high frequencis to avoid the pot entirely, so they are not attenuated at all, and the signal has more treble than signal would have had if it had passed through only the pot. -Chris

4/5/2000 6:34 PM

ChrisM

Re: what does the cap actually do?

A capacitor is like a resistor that only works for low frequencies. At DC levels, a capacitor is an open circuit, looking like an infinitely large resistor. As the frequency of the signal increses from DC, the resistance(or impedance as they call it when you're dealing with capacitors and inductors) decreases, until the capacitor looks like a short circuit at high freqeuncies. If I'm right, bright caps are wired in parallel with the pot. Impedances in paralllel look most like whatever impedance is smaller, so at high frequencies the capacitor and pot combo look like a very small resistor, and at low freqeuncies the cap and pot look like just the pot. So, in short, the capacitor is allowing the high frequencis to avoid the pot entirely, so they are not attenuated at all, and the signal has more treble than signal would have had if it had passed through only the pot.

-Chris

Replies:

JR. Re:other substitutions? -- 4/5/2000 7:13 PM