Wah wah pedal details
A single component (capacitor, resistor or inductor) does not have a characteristic frequency. A combination of them may have one. For a simple example, a low-pass filter made of a resistor and a capacitor has a cutoff frequency around 1/RC. Thus you can change the frequency by merely altering the resistance, which is nice as variable resistors are simpler and cheaper than variable capacitors.
Similarly, the capacitance in a wah wah pedal is not changing. The resonance frequency is changed simply via the variable resistance.
Things about my body I'm afraid don't happen to anybody else
The node doesn't accept any more WUs, so here's my take on the topic. It may have interesting material for another node though. Plz msg me if you find it interesting and nodeworthy.
The point on the forehead that killermonkeys refers to is most likely the third eye, also known as ajna which is one of the seven Chakras. According to some Yogic scriptures, a strong ajna chakra is a sign of early conscious and spiritual development, and it can be leveraged to strengthen the other chakras as well.
My personal encounters with the ajna chakra
When I was young, around 10 years old, I could feel the presence of objects near the center of my forehead, without seeing or touching them. It was a kind of sixth sense. The effect was more pronounced for artifial materials like plastic, and barely noticeable for natural ones such as wood.
A few years later I had almost forgotten the sense when I learned of the third eye. When I started meditation I could often feel the same sensation when I entered a state of promoted awareness or focus. In fact, now that meditation is a significant part of my life, I often get into that state when working, even now that I'm noding. Enjoying a movie, a piece of music or a book can also trigger the feeling, and usually it sets me in the mood for meditation afterwards.
In a Buddhist meditation class I was mildly disappointed to learn that nobody else there was experiencing the same. My teachers told me that it can be a valuable thing to explore, for instance as a point of focus in insight meditation. I was wary of being too attached with a single point, but when I got into deeper meditative levels, the point-focus dispersed quite naturally. It was an enjoyable road into the rest of meditation. The pleasurable sensation would sometimes spread throughout my head and even further into my body. An intellectual orgasm in a very literal sense.
The curse of being gifted -- notes to mandrax
I can say the exact same thing about myself. I was fortunate in that I went to International Baccalaureate and from there to Cambridge University (I'm from Finland), where I felt very much at home and life was interesting and challenging. But since my graduation I've felt that I have no more dreams -- which BTW is sometimes considered the point where you're an adult :(
Recently I've read a lot about the INTP personality type and I've identified myself as one. One of the problems of being INTP is that you get excited about a subject, such as playing a new instrument, but once you get sufficiently good you lose interest, because it gets harder and harder to become any better. Fortunately there are so many different things to do within music, for example :) But anyway, you end up in this cycle of chasing novelties and never being truly happy. I guess one longer-lasting source of mental stability for me is Buddhist meditation and yoga.
This year, after a couple of years of odd jobs such as teaching, I'm starting a PhD in particle physics, and I wonder if it's the right thing for me. I already feel I'm not as passionate about it as I should. On the other hand I remind myself that doing a PhD doesn't lock me into an academic career.