Audio File Types and Why You Should Care
You’ve heard it before. You might not be able to describe exactly what it is that’s different about it, but you know it when you hear it. To some, it’s barely discernible. To some, it’s an affront to our hearing. What is audio compression and why should we care?
Allow me paint a picture for you:
Let’s say you own a log cabin, but you have to move, and it’s very important to you that you have YOUR cabin at your new location. Moving your entire log cabin as it stands is not a task that you can accomplish even with the help of your truck and trailer, because it’s just too heavy. You decide that you have to saw off parts of the cabin, so you start by taking pieces and corners off that aren’t crucial to the building standing. You remove little ornaments and fixtures, etc. You pick and choose the parts that really make your cabin work. You burn what you cut out, you lift your little house into your trailer, and you leave (just go along with me). Once you arrive at your destination, you unload your cabin and it looks essentially like it did. Albeit it’s a little leaky, and a bit drafty, and the ceiling is much lower… but it’s still habitable.
Now imagine an alternative. As you were looking at what pieces of your cabin you were going to saw off, you instead started taking measurements and writing down instructions on how to rebuild those parts of your cabin you’d be removing. You get the cabin light enough to lift and load into your trailer, and burn the parts you removed. Once you arrive at your destination you begin replacing what you removed until it looks nearly identical to the original cabin!
Lossy codecs are the hack and saw method, and lossless codecs are the remove then rebuild method. Does one of those methods sound better to you? (ha ha… haaaaa…. puns…)
That being said, there are some great lossy codecs out there that are very smart with what they remove from the file, picking things that are unimportant to human hearing, and often in a way that psycho-acoustically will make us think that less audio is missing than truly is. It’s some crazy digital sleight of hand in both cases. To put it back into our analogy, it’s as if you were a master architect and woodworker and could hollow out the logs in your house or something.
Here’s the REAL issue though with lossy files, which Thaddeus addresses in the video. Going back to our first log cabin, let’s say you want to move again. After sawing a bunch of stuff off, trying to move your cabin again in this state is going to cause some additional damage. It’s so flimsy that lifting it back into your trailer causes some logs to crack and some pieces to fall out of the trailer as you are leaving. By the time you get to your newest location, your cabin will still stand, but it’s really beat up and ugly, with gaps all over the place. Your new neighbors even start to wonder if you stole it.
This is what happens when you try to work with a lossy file and then re-compress it. For example: someone ripping a beat off of Youtube and then mixing their own voice with it, and then putting it up on Youtube AGAIN. The Youtube audio codec thats being applied has already done its damage to the original beat, and the pieces it sawed off are not coming back. So when you get your mixdown with your vocal over it, sure you may have bounced it out as a WAV file, but Youtube is going to run the same codec on that file again and remove some more stuff. This double compression after the fact is where a lot of more noticeable destruction happens to audio.
Thanks for reading, we hope this was helpful, and if you have any other audio topics you’d like us to address for a video or article, shoot us a message.
-Christian
