How to Make Spotify Happy
With physical audio media in its twilight, streaming has become the primary way to distribute music. A wonderful side effect has been the end of the loudness wars, because streaming services like Spotify turn levels up or down as needed to attain a specific, consistent perceived level—squashing a master won’t make it sound any louder.
However, the “garbage in, garbage out” law remains in effect, so you need to submit music that meets a streaming service’s specs. For example, Spotify prefers files with an LUFS of -14.0 (according to the EBU R128 standard), and a True Peak reading of -1.0 or lower. This avoids adding distortion when transcoding to lossy formats. If the LUFS reading is above -14.0, then Spotify wants a True Peak value under -2.0.
Fortunately, when you Detect Loudness for a track on the mastering page, you’ll see a readout of the LUFS and LRA (a measure of overall dynamic range), as well as the True Peak, RMS (average signal level), and DC offset for the left and right channels. Fig. 1 shows an example of the specs generated by detecting loudness.
Figure 1: Although the LUFS reading meets Spotify’s specs, True Peak doesn’t, and the RMS value of the left and right channels isn’t balanced.
Note that this hits Spotify’s desired LUFS, but the left channel’s True Peak value is higher than what’s ideal. This readout also shows that the average RMS levels for each channel are somewhat different—the left channel is 1.2 dB louder than the right one, which also accounts for the higher True Peak value. This may be the way the artist wants the mix to sound, but it could also indicate a potential problem with the mix, where the overall sound isn’t properly centered.
A simple fix is to insert a Dual Pan into the Inserts section. Use the Input Balance control to “weight” the stereo image more to one side for a better balance. After doing so and readjusting the LUFS, we can now give Spotify exactly what it wants (Fig. 2). Also note that the left and right channels are perfectly balanced.
Figure 2: The True Peak and RMS values are now identical, so the two channels are more balanced than they were without the Dual Pan.
A Crucial Consideration!
You don’t want to mix or master based on numbers, but on what you hear. If you set up Dual Pan to balance the channels, make sure that you enable/bypass the plug-in and compare the two options. You might find that balancing the left and right channels not only accommodates Spotify’s requirements, but improves the mix’s overall balance. If it doesn’t, then leave the balance alone, and lower the track’s overall output level so that True Peak is under -1.0 for both channels (or under -2.0 for LUFS values above ‑14.0). This will likely lower the LUFS reading, but don’t worry about it: Spotify will turn up the track anyway to reach -14.0 LUFS.
Coda: I always thought that squashing dynamic range to try and win the loudness wars made listening to music a less pleasant experience, and that’s one of the reasons CD sales kept declining. Does the end of the loudness wars correspond to the current music industry rebound from streaming? I don’t know… but it wouldn’t surprise me.