Audio come in several different shapes and sizes. Bit Depth is one of the more important sizes - It determines how much dynamic range you can get from your audio.
Don't confuse it with Bit Rate; they are two different things - Time for an analogy. If you have a river (Okay, not many people can relate to actually owning a river, but you can pretend you are horrendously rich so you can afford to buy one to understand this concept better. It's fun, right?) the bit depth would be the depth of the river - how much water it is capable of holding, while the bit rate would be how fast the water can flow through a section of the river in a second. But yes - for this article I'll explain about bit depth and why it's useful to know about it.
From lo-fi to hi-fi
Inevitably, technology has to start out small - so it was that many of the original samplers began with 4 bit and 8 bit sound qualities - not exactly ideal for immense, dynamic soundscapes, but it did the job for much of the early electronica. In fact, some people love the lo-fi-ness of these samplers that they'll go out of their way to reduce the quality just to replicate that old school sound.
Evolution of quality
But as with all technology, it's not long before the Japanese make it better.
Samplers such as the Akai S1000 broke the mould, with the advent of 16 bit audio bit depth and features such as time stretching allowing the birth of jungle music as people could finally speed up their amen breaks to their hearts content.
Incidentally, do you know what's important about 16 bit? This is the quality of CDs, allowing people to hear much more from their music...
16 bit CD quality"Why does it have to be 16 Bit?" you might ask - well, it doesn't, but Sony insisted on it. Philips and Sony, the two companies developing CD technology were arguing about 14 bit or 16 bit respectively - Sony obviously won, but Philips vowed revenge. Not really - they just made their 14 bit Digital/Analogue converters increase their quality by oversampling, and everyone lived happily ever after... or did they?
Data size
As internet connections are getting better, hi definition audio is more common. The website Soundcloud and even the popular music streaming program Spotify are now providing 160kbs minimum quality mp3s to their users. There must be a reason, right?
Is it possible to hear 24 bit?
There is a reason people have been upgrading to 24 bit systems. Most current digital to analogue audio converters only have a maximum dynamic range of about 120dB. The Rule of Thumb says that for every 1 bit of bit depth, you get another 6dB of dynamic range. If your maths is as sharp as a sawtooth wave, you should be able to figure out that 16 bit equates to 96dB of Dynamic range - not filling up the possible range - there's another 24 dB of potential dynamic range there. With 24 bit, that equates to 144dB of potential range, filling it up nicely and definitely making a difference - your massive bass drops will hit 25% harder with 24 bit. That's 25% extra punch-in-the-face from every kick drum and 25% extra headroom for moving between quiet, delicate harmonies and intense electronic breakdowns.
What is 32 bit floating?
As audio technology pushes even harder to replicate the real world, higher bit depths are called for. 32 bit and even 64 bit audio are now available on audio programs such as Sonar and have been for several years now.
You might wonder what the point is if only 120dB is available and 24bit is already 24dB over that limit - well that 120dB limit only applies to most sound cards. ASIO sound cards, for example, allow much higher bit rates to shine and as technology develops, you can bet on even higher bit depths becoming standardised.
So - are you going to stick with the old school or spring for that extra punch-in-the-face-ness that the higher bit depths offer?
