Analogue Audio
What is Analogue Audio?
When we capture sound, we do so either in the Analogue or the Digital realm.
Let's stick to analogue for now, as the Digital Audio realm is going to be a whole thing by itself.
Analogue audio is basically audio, in the form of electricity.
Let's explore.
When we sing into a microphone, we are transferring physical sound (which we now know is compression and rarefaction) into the microphone diaphragm. This moves forward and backward (much like a speaker does) and where a speaker converts an electrical signal to physical sound, a microphone just does the exact in reverse!
Since a speaker and a microphone work in almost the same way (but in reverse) there are multiple cool inventions out there by audio engineers! These include but are not limited to:
- Wiring an old phone into a microphone
- Wiring an old speaker cone in reverse, as a huge microphone to capture the kick drum
- Wiring an old microphone in reverse to create a boxy, small, bad sounding speaker
The result is a (very tiny) electrical signal sent out of the microphone's output through the cable, to whatever receiving device on the other end - usually a mixing console or preamp..
We can also just send a signal out of the mixing console, or a digital keyboard, iPod, or any playback device to a speaker, and the sound signal travels as analogue audio which consists of electrical signals. The cable used might be the same, an XLR cable, but the signal coming out of the console is MUCH MUCH louder than just the signal coming from a microphone!
The output of a microphone and an iPod, while similar in the fact that they are electrical, differ in their voltage or amplitude.
This is referred to as Mic Level, and Line Level.
Mic Level and Line Level
I will point you to an article written by professionals in the industry, and it's a short detour to learn more about Mic level, Line level, and even Aux level!
In review, mic level, line level and aux level is the quick way of determining how strong a signal is, and therefore we should be mindful and think about how we are getting signal from one device to another!
Line level is MUCH hotter (louder) than mic level. Therefore plan and know how things are plugged in before muting/unmuting channels.
In example, if a line level input was plugged directly into a microphone preamp and the gain is turned up for a microphone level signal, the input will clip and be very loud and can damage equipment and/or cause hearing loss!
Now you are equipped with knowledge about what Sound really is! Both in the physical form as well as the analogue form in which we will be transporting sound and manipulating it, and directing it back to physical.