Thanks is a wonderful thing to give and receive. It's like the left brain of love — the actions to the sentiment. Giving and gratitude are the supporting cast of our favorite fuzzy feelings.
Today I give thanks for the engineers in the middle of the last century for their work making electrified sound more realistic and engaging. I give thanks that they gave life to the music we take for granted today.
Before World War II, the best minds in the country were focused on capturing and reproducing sound in the most realistic way possible. From Alan Blumlein's insistence that the sound of actors in the movie follow their movements across the screen, to his eventual creation of many different stereo recording and playback techniques, to the tireless brains at Bell Laboratories trying to make electronic transmissions sound better when they traveled across long distances, the era was an explosion of experimentation and discovery.
Lately here I've been talking about how amplifiers work. They take a small signal of music in its swinging AC form, and directly connect that to elements that swing very large and very fast. They take a quiet representation of music and make it louder; they take little ripples and turn them into big waves.
I went over harmonics, and how humans are fond of second-order harmonics in nature, tubes and instruments themselves. A harmonic is when a single note contains higher and lower-pitched elements that help it define the complete sound. A violin and a piano may be able to play the same note, but thanks to harmonics, they will never sound the same.
Today I want to focus on power. You may think that the playlist on your iPhone and the link between the source and the stereo creates the music, but you'd be wrong. The quiet music signal from your phone merely serves as a guide for the amplifier to make loud music. It's the original picture, and the amplifier is the tracing paper, hand and pencil.
An amplifier takes power from the wall and lets the signal from your iPhone modulate or guide the amplifier's amplifying elements to recreate the music.
Music on your phone is similar to the power in the wall socket, except it's a lot lower in electric voltage and intensity. Also, the wall power doesn't modulate — it is a steady tone. In America, wall power is a steady 60Hz, and in Europe and elsewhere it's 50. Those are bass notes! Really low ones.
So the power in the wall, if simply amplified and recreated, would sound like a really low synthesizer note. It's not until it hits the amplifier that it is spun and changed into glorious music.
There are two common ways that amplifiers use wall power to create music. Next week, I'll dive into the difference between "linear" power supplies and "switch-mode," and the differences in the character they impart on the sound. Remember, we'd have no music if we didn't have power to build it up with. And any error in recreating the music can change how it is enjoyed. Power is a very important part of all of this. Stay tuned.