The top 2-5 dB of every sound is basically garbage
The top 2-5 dB of every sound is basically garbage
Longtime readers of Jamie’s list know that I’m a big fan of limiting / clipping / tape at the channel level. As I alluded to in the linked post, you can shave off the top few dB of any and every channel without noticing it, and doing so can cause things to work out better in the master bus. Our friend Leigh Harrison summed up her experience with this succinctly:
If I use a clipping plugin on every channel of a drum kit I can get the same perceived volume with about 6db less peak level.
The benefits of doing channel limiting / clipping / etc are readily perceptible. But why is this so? Why can we just shave off the tops of waveforms without ruining our music?
The answer is that the top 2-5 dB of every single channel of audio is basically garbage.1 Let’s look at some examples!
BASS
GUITAR
VOCAL
SNARE
All the stuff above the red line in each of the second pictures is extraneous crap. This is stuff that in a lot of cases you wouldn’t even be able to hear if it were removed, but which adds lots of unnecessary extra energy into downstream processes — compression, limiting, etc — causing those processes to overreact. And in the cases where you might be able to hear the stuff above the line being shaved off — vocals, guitar — it would be better without it.
This is why people loved recording on tape: tape munches transient information! When you think of a classic “tape sound” in a recording — warm, relaxed — a huge part of the reason for that is that it gets rid of this garbage transient information for you, which as noted above results in not only less random transient crap but also downstream compression and limiting that behave more naturally / less erratically.
Indeed, it does this to a fault — tape can also remove some of the transient information that you might actually want. This is why most people have switched from tape to digital recording — aside from tape machines being a nightmare, we have much much more control in digital recording over what information we choose to throw away — instead of leaving it to a process over which we don’t have complete control. We can capture all the detail, and then make intentional choices later about how best to treat the resulting waveforms.
And we should definitely do that! It’s a rare audio track that wouldn’t benefit from a little transient shaving. Pretty much every waveform has a red line — if you can find it, and throw away the stuff above it, your recordings will improve.
Chop chop — jamie
The top 2-5 dB of tracks recorded on tape are much more often not garbage, for reasons that we’ll get into at the bottom of this post.