In which Ian probably goes too far with his analogy explaining compression using sponges. And in which Jon describes the concept of “sloppage headroom” and inter-sample peaks, and in which we also discuss:
- Why lossy data compression doesn’t affect dynamics, except
- When it does. And
- Why dynamic compression doesn’t affect lossy compression quality, except
- When it does. Plus
- mp3 or AAC ? VBR or CBR ? Do we care ?
- The ultimate mp3 encoder stress-test
Links
Compression versus compression - the infographic
TMS #21 – Why digital “resolution” doesn’t exist – because dither
The Coffee cup analogy to audio headroom
Mastered for iTunes & intersample peaks - VIDEO
I'm such a freak that I went back and RE-listened to the Dither Episode.
Ian, I love the podcast and have listened to all 36 episodes. I get it with audio compression versus data compression but I'm thinking that there is another form of data compression. If I have a client that is going to send me a project to mix with say 35 audio tracks recorded at 48K 24 bit that can get to be a pretty large project to transfer to me via Dropbox. So, if they right click on the project folder and "Compress" it before sending it to me, what affect, if any, does this have on audio files? To extend the sponge metaphor, if you want to ship a hundred sponges to someone, you compress them to a fraction of their size before you put them in a box to ship. When someone gets that box of sponges, all they need to do is put them in water to get them to expand to their normal size. So when I get files from my client that have been compressed on their computer, when I uncompress them, will they be altered in any way where it affects the audio?
This is the lossless "ZIP" part of the discussion. the audio is not affected but it is also not readily usable without extracting/unpacking the zip.
OK, weird analogies aside, there was some interesting content there. FWIW, I think I understand compression better than sponges in gutters LOL! Perhaps you underestimate many of your listeners.
Anyway, my suggestion this week is that you could perhaps touch on the difference between "leveling" with compression and leveling with either level automation or fader rides (including the "automated automation" type fader ride plug ins).
There are those who feel its the same in the end, and I say, generally speaking- not so much........ Kind of two different things really IMO. Whatcha think?
Ian and Jon, I've listened to all episodes so far and they're pretty informative allover. One thing though is getting a bit annoying: the (seemingly?) total lack of direction in the way the conversation is built up. I would expect there to be a sort of script where all subjects to be touched are listed in a logical order? The way it is now, it sounds like a random conversation that could go in any direction at any moment. Some may like it that way, but for me at least, a little more structure would be nice.