Understanding Variant and Modifier tracks
The Track Browser is where you go to choose your tracks manually. When you first load the Track Browser, only recently added tracks are listed. This list is a good place to start if you are on the radio often and are looking for the newest and shiniest tracks.
Most of the time, though, you'll want to select tracks from specific categories. When you select a category, you'll find the expected tracks for that category (logically enough) but you'll also find more tracks from other categories included in the list, offering you some more options. These additional tracks come in two varieties: Variant and Modifier.
Variant: Variant tracks are rhythm tracks from other categories that also offer a brain shift effect similar to the category you've chosen. These offer more options to fine-tune your stimulation level and the resulting effect.
For example, you may be searching for a focusing track to use but decide when looking over the variant options that a Brain Boost track is a better fit for your goals.
When you choose this variant track the focus ambient tracks will remain, thus offering you ambient tracks that can enhance the focusing effects of the variant rhythm.
Modifier: Modifier tracks are ambient tracks from other categories that are compatible wih the category you've chosen. When you choose a rhythm track category, ambient tracks from that same category are sorted. At the same time, you'll also find additional ambient tracks that have a modifying effect on your chosen rhythm track category.
For example, you may choose a focusing rhythm track and then add a calming modifier from the ambient track list. This adds a slightly more calming element to the rhythm track's focusing effect and may be a better fit for you than choosing the typical focusing ambient track with your rhythm.
Remember: You can choose any rhythm track to go with any ambient track when you are in manual mode (I'll Choose My Own) using the Track Browser. But including variants and modifiers in the category sorting makes it easy for you to cross categories while offering you some guidance when choosing.
So, go ahead and mix it up and choose some variants and modifiers for your next mix. Just remember to save your favorites because there are tens of thousands of track combinations and it may be difficult find this combination again.