As much as I'd love to get into the nerdy details of why you don't want your master to be too loud, I'm gonna try to keep this post as simple as I can in hopes that it will resonate with more people.
If you've been making records for any length of time then I'm sure you've heard about the “loudness wars”. Basically for the last 20 years everyone wanted their record to be louder than everyone else's so that it would grab your attention and sound more energetic, and it totally works! When listening to a great sounding record then switching to a louder record, it immediately grabs your attention, even if it doesn't sound as good, when it's louder it usually feels more energetic.
People rarely listen to CDs anymore and even digital downloads are becoming a thing of the past. Streaming is king and the rules have changed. If you have a super loud record then the streaming services will just turn it down.
It all started in Europe when people became fed up with television commercials (adverts) that were a lot louder than the actual content they were watching. You know, when you're watching your favorite TV show and then a mattress commercial comes on and blasts your face off screaming about how their prices are at ROCK BOTTOM!!! For decades there have been rules put in place that govern how loud broadcast content can be, but those were based on peak level values rather than the average overall loudness. Remember how loud content grabs your attention and gives a feeling of excitement? Well, advertising agencies know that too, so they “cheated” the system by limiting the audio so hard that the average overall loudness was much louder than the scheduled programing you are watching but without going over the peak level requirements. To combat this the European Broadcast Union (EBU) came up with a new way to regulate and meter loudness.
Why It's Relevant
Youtube was the first online platform to start level matching content automatically and it makes sense. Think about it, if someone was watching a video shot on an iPhone of someone whispering and then they switched to a Skrillex music video they'd blow up their speakers or get hearing damage! The YouTube servers analyze the loudness of all uploaded content, if it's louder than their standard, they simply turn it down. If it's too low then they bring it up as much as needed, but they don't limit or compress the audio (yes I know it has digital compression, but not dynamic compression). Spotify, Apple Music and I'm sure most of the others do the same thing, if it's too loud, they just turn it down.
The Sweet Spot
You don't want your record so loud that they turn it down, but you don't want them to be too dynamic either, both will sound smaller than a record that's right in the sweet spot. Apple Music, Spotify and YouTube haven't officially released what they're loudness guidelines are, and they are all a little different, but they're all very close.
Traditionally the sonic fidelity of a master has suffered when volume is the ultimate goal. I hope that as our community starts to understand how streaming services affect the music we create, and that we can see it as an opportunity to make records sound great again!!
Check out the video below for an example.
*Volume normalization can be turned off in Spotify by going to "Preferences->Show Advanced Settings->Set the same volume level for all songs"
Here is are the songs used in the example