As we explored last week, sound is pressure variations in the air and that's
continually variable. It's not discrete steps, but constant.
The computer can't understand that kind of information.
Only thing the computer can deal with is strings of numbers.
Things represented in 1 and 0s, what we call binary information.
So, there's a process to go from the continually variable sound into the
stream of ones and zeros. And that process is called a sampling
process which we talked briefly about before.
But I'd like to go into a little more depth here.
And before we even get to sampling I want to talk about binary information.
You're going to find that so much of what you deal with and so many of the numbers
you see when dealing with music Production is really based on this kind
of information. So, binary information is based primarily
on the bit. And a bit is a single, kind of, memory
location, and everything comes down to bits.
In a single bit, is a 1 or a 0 and that's all you have.
And every number is collections of those ones and zeros.
So the number of bits, determines the maximum number of states, or the biggest
number that you can represent. If we have a single bit, we can represent
two things, on or off. Maybe heads or tails on a coin.
or on or off of a switch or a number from 0 to 1.
If we want to represent larger numbers, we have to start collecting bits into
words. And a word is a, a collection of bits.
And very often, in the computer, we make a standardized kind of collection.
You'll have MIDI data, for instance, uses, commonly uses seven bit words.
Or if we're dealing with digital audio, we use 16 bit words.
So it's important to know kind of how many values you can represent with a
specific number of bits. Or with a specific word length, how many
bits using a, in a particular word. If I have a one bit word it's going to be
two values. If I have a two bit word we can actually
represent four values. And it's really just all the permutations
of ones and zeroes with that many bits. So if I have a two bit word, we have
values of zero, zero, zero, one, one zero or one one, so we can represent four
things. So if I wanted to represent the seasons
of the year, I could use a two bit word and get Spring, Summer, Fall, and Winter
no problem out of that. But if I wanted to represent something
larger, I would need a longer word length.
Now, it's good to know how to kind of know with numbers how many bits, what's
the largest number you can represent. And it's always two to the power of the
word length is going to give you the number of, numbers, the value that you
can represent. So take it on yourself, let's do a little
quiz here. What can you get, how many values can you
represent, if you have a 2 bit word? What about a four bit word?
Seven bit? Eight bit?
16 bit and 24? You're going to see that every time you
add a bit, you actually double the number of values.
And it gets very large very quickly. Now when we're representing sound in
digital audio. You're going to find that there's a
couple standards, CD standard is a 16 bit word.
And when we start measuring sound to create, to, to create digital audio,
we're going to find that we make many, many measurements very fast.
And each one of those measurements has a specific word length.
it's also known as the bit depth, but I like the term word length better because
words have length. bits don't really have depth, do they?
So CD standard, is 16 bits. So that means every we measure sound,
we're using a 16 bit word. And that really is a great number.
We can represent, I mean everything you hear on a CD, is done in that quality but
in the studio we tend to use a higher word length.
And maybe 24 bit would be a great setting for when you're recording.
And what that gives you is a wider dynamic range, so we're going to find
that the two,two,two really important parameters in digital audio.
What we're talking about right now is word length is related to amplitude and
the one we're about to talk about is the sampling rate and that will be related to
frequency. So, word length, the longer the word
length, so if I have 24 bit word length I have a wider dynamic range.
And that is going to really, it's not going to be that perceptible, but what it
does allow you to do is not record at such a high value.
And we noticed that when we're recording we had to set our input gain very
carefully. And we wanted to get as loud as possible
without clipping without ever distorting. Well if we're recording at 24bit, we can
actually record a little bit quieter and still get a good recording.
And that's the benefit because you're not going to be so close to distorting as
you're recording. So I really recommend when you are
recording, record at 24 bit and you might want to take a moment to go into you DAW
or into your audio interface preferences. Or even look for the switch on the
outside of your audio interface to see just how you can convert between or how
you can set the interface with the DAW to work in 24 bit mode.
It's an important characteristic, an important thing you want to decide before
you start. whenever you're working with these
digital audio principles, you want to make sure you set them once, and then use
them throughout our project. There can be small issues if you do
change these settings in the middle of a project.
So you want to create kind of a standard for yourself.