I have two questions... 1. I have seen that different value capacitors in an amplifier circuit, sound different... For example, an amplifier circuit with a 470uf capacitor, has more bass, and treble... A 1000uf capacitor, has a uniform distribution of frequencies more or less... A 330uf capacitor sounds like it has more focus on the vocals... mid range... So, what is the real reason for them to sound the way they do? In physics or mechanics or electronics sense... 2. In an electric guitar and amplifier setup... Introducing a resistor value, between the amp and the guitar, changes the way the guitar sounds... I have tried lots of values, some of them are, 330k, 470k and others in that range... Why does this setup, act like equalizers? The resistor i connect is in the positive terminals, not ground ones... This seems to work in a cd player to music system too... The resistors become like presets of music equalizers... I understand we are changing the impedance, but why do they sound so different at different impedances...? Circuit: 