Continuing with the story of power supply importance in amplifiers, we arrive at an interesting point; the idea that the original musical signal gets translated into something related yet different. Let me give you an example. Think of a phono cartridge on a turntable. We know that as the needle is dragged through the record's grooves it moves back and forth. When this happens it brings a small magnet close to a coil of wire and electricity is generated in direct proportion to the needle's movement. What comes out of the cartridge is an electrical translation of what's on the grooves of the record. We can't 'hear' the grooves, we can only hear the translation or the electrical representation of those grooves.
If you ponder this for a moment it might strike you how miraculous and magical this process is. Hold a black vinyl album in your hand and look closely at it. Tiny wiggles embossed onto a piece of plastic. Imagine handing this to someone who had never been introduced to such a thing (I always picture someone from the 1700's). What would the chances be they could figure out the purpose of the small grooves? And even if you explained there was music captured in those grooves, that'd be a hard sell. But none the less, we know the secret of how these wiggles get translated to music. Yet, when we listen to the translation through an amplifier we do not hear directly what was captured. There is another translation necessary: perhaps several before we hear music.
The small electrical signals generated by the phono cartridge are used to turn our valve on and off, releasing more or less of what's in the amplifier's power supply. We are not listening to the actual signal from the cartridge. Rather, we are listening now to the power supply itself.
More tomorrow.
