Things are called a little differently in FL Studio
I want to quickly clarify some things if you are used to another DAW because you may be confused when you look at the FL Studio mixer.
A CHANNEL is called an INSERT in FL Studio.
A SEND is called a SLOT it FL Studio.
You also have to know that in FL Studio, instruments are placed in a thing called the Channel rack. So each instrument has a channel, which is routed to the Master-Insert/Output by default.
Obviously this is bad for mixing so you need to take control manually.
Why to use submixes
A submix is a group of signals bundled together into a single signal.
You can use this if you have a group of instruments to which you want to apply the same effect, like an EQ or a Reverb. You can apply the effect on the submix instead of each individual instrument. It's very useful if you want to work with layered sounds. In my example I built a Supersaw kind of sound that consists of 3 instruments.
Routing instruments in the Mixer
In FL Studio, when you add an instrument to the channel rack it is always routed to the Master Insert/Output by default. This is unusual because most common DAW's automatically route to a new channel when you create a new track.
In FL Studio, you have to do this manually. Luckily, like most things in FL Studio, it's quick. Activate your instrument by clicking on its name in the Channel Rack. The plugin appears. On the top right there is a little box in which you can click and drag to select the #number of the Insert to send this instrument to. You can see this in the image below.
To make things worse, it says "Track" underneath this little box, and the tool tip says "Target mixer track". So Inserts are also called Tracks. Seriously FL you need to grow up. Long time users won't care about this but how is any new user supposed to think this is reasonable?
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| Here it says "Track", which means the same as "Insert" in FL Studio. |
Alternatively, you can select the instrument, then the Insert/Track in the mixer and use the shortcut CTRL + L, which I think is faster.
After passing through the Insert, the signal now goes to the master. This can be seen by the circle around the knob in the picture above (and the cable that goes there).
Creating a submix in FL Studio
To route the 3 Inserts into a submix, you first have to disable the signal flow to the master, so you click on the little green arrow above the knob on the Master Insert/Track/Output. This stops the signal flow. Do this for all the inserts you want in your submix.
Now pick any Insert you'd like to use as your submix and rename it by middle mouse clicking on it.
Now select the Inserts through which your instrument signals go and simply click on the white upwards arrow of the Submix Insert (image below). A cable appears, showing the signal flow.
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| With the insert selected click on the arrow to route to the submix. |
The signal now goes into the submix. Do this for all of your instrument inserts. The submix still flows to the master by default, but you could change that if you wanted to.
Adding Effects to the submix
You can now apply your effects to the submix slots. In my case, I use an EQ to get rid of the muddy lower frequencies.
I suggest you use submixes as much as you can because it allows you much better control over volume and effects. It also encourages you to layer instruments which is mostly good practice.
