Comparing Level to the Competition
You’re watching TV late at night. When you turn it down, you don’t want quiet parts like speech or whispers to get any quieter than they are — you only want the loud parts to get quieter. With Level, that is exactly what happens.
When you’re listening on a bus, and you turn it up, you only want the quiet bits louder — you don’t want the gunfire and the explosions to get any louder. Again, with Level, that is exactly what happens. There are other approaches to solving the loudness problem. So why is Level so much better?
iTunes’ Sound Check analyses the overall average loudness of a song and uses that to work out how much to turn songs down by so that they are all the same loudness overall. The result of Sound Check is that all songs are all made slightly quiet.
When you switch from song to song, the overall loudness is the same. But soundcheck doesn’t stop the quiet bits from being overly quiet or the loud parts being excessively loud. So when you are on a bus for instance, it doesn’t really help that much. Level, on the other hand, gives you total control of the loud and quiet parts. All content (not just music like Sound Check) is given consistent loudness, whether it’s a Skype call, a film, a YouTube video, or a game soundtrack. So Level includes the benefits of Sound Check, but for all audio content not just music, and with control over the extremes of loud and quiet sections.
Normalisers scan entire audio files in advance to find the peak, and then turn each song up by exactly the right amount so that the peak of the audio hits the loudest your device is capable of when you have it playing at full volume. In theory, this approach normalises all the audio without damaging it too much. But in practice, it isn’t that useful because it only works for pre-recorded content (not live sound), and the peak of a song in general bears no relation to the overall perceived loudness.
Just because the highest peak in every song is the same doesn’t mean that every song now sounds consistent. Switching between different songs will still be a loudness mess. Level takes into account the actual perceived loudness and can therefore make all your songs consistent — at the same time also ensuring that the audio never goes excessively loud or overly quiet. All this, without damaging the sound.
Downward compressors are by far the most popular kind so I’ll describe those, but these concepts apply to all compressors. With a downward compressor, when the sound goes above a set threshold the compressor kicks in and turns the audio down. When the sound has stopped being above the threshold, it releases, and the audio is turned back up again.
Compressors work against the audio. Louds all become the same. And just after each loud peak, quiet bits are made too loud, so you get a classic negative side artefact called pump. This fighting the audio can sound really yucky. It can sound ok, but requires a pro engineer fiddling for hours, and many people still don’t like the results!
Level works with the audio whenever it can, so that you don’t get annoying, unnatural pump. With Level, the overall feel of micro dynamic is kept just as the artist intended. The result of our approach is that Level sounds exactly like the original, except, that the range between quiet and loud is now what you ask for via its sexy UI — not how you were forced to have it with volume, which doesn’t alter the range at all.
Auto-gain also works against the audio, and makes audio sound like it is seasick; constantly undulating up and down and trying to rebalance itself. Level achieves the same ideal, but stabilises the effect by waiting and only changing when the change cannot be noticed. This way you get the benefits of auto gain (easy overall listening) without the nausea!
Level isn’t just Sound Check, normalisation, compression and auto-gain stuck together. It takes a more intelligent approach to the audio processing, and a revolutionary approach in its user interface. Stay tuned for another post on how Level’s UI joins science and usability at the hip, as we reveal more details of the new design.
