There were some questions about capacitance filters versus inductance filters, this is what I have found out and what I still want to know. A capacitor is a high pass filter, allowing high frequencies to pass and blocking low frequencies, proportionally. An inductor is a low pass filter, allowing low frequencies to pass and bocklng high frequencies, in proportion. A choke is an inductor. A resistor is the same for all frequencies. First order filters are made of a combination of these circuit elements, RC, RL and LC. Each pair can be high pass or low pass, depending on their order. What makes a filter high pass or low pass? In each diagram, the input is at the left, and the output is at the dot. The most common is the RC filter. The capacitor is high pass. What is note worthy is the low pass filter is made from a high pass capacitor. On the left, high frequencies are passed to ground, leaving low frequencies at the output, making a low pass filter. On the right, the capacitor being a high pass filter, allows high frequencies to reach the output. Next is LR. Similar to RC. The inductor is low pass, so the filter on the left allows low frequencies to reach the out put. The filter on the right is high pass because the inductor passes low frequencies to ground. Last is LC, common to Fender amps. The LC filter combines the high pass capacitor with the low pass inductor. The filter on the left is low pass because the low pass inductor allows low frequencies to reach the output and the high pass capacitor passes high frequencies to ground, kind of redundant. The filter on the right is high pass because the high pass capacity allows high frequencies to reach the output and the low pass inductor passes low frequencies to ground. Which of these filters are common to fender amps? The R, C and L are used to establish the time constant or cutoff frequency for the filter. Here is the question How do you rate the amount of filtering in an amp? The amount of capacitance? The amount of inductance? The amount of resistance? There are no units for the amount of filtering, are there?