# Changes to Sidechaining in Reaper 7
This [Reaper Blog video](https://www.youtube.com/watch?v=xmuwz6JsvIU)

* FX Sidechain: allows drag/drop sidechain creation to FX in containers, floating windows
* When creating sidechain via drag/drop to FX, always add/route to new track channels.
* Reconfigure pin mappings for sidechain if FX has 4 inputs.

1. Drag and drop example: kick to bass channel. 1/2 from kick routed to 3/4 on bass.
    * If we drag and drop a snare too, it routes to 5/6, not 3/4.
        This is not how it used to work. Sometimes we want the snare to also go to 3/4.
    * If we shift-drag multiple tracks I/O to a window, it sends to the same channel pair.
    * If send to 3/4 is already done, if we want to reuse the 3/4 channel, we can use the mixer, where we can see the sends, and drag a send to the plugin.
    * So drag/drop increase channel count if dragged from IO button, but not if dragged from mixer sends area.