In mixing terms, using an effect as an insert versus a send are two different things. Each has their own specific purpose, so let’s take a look at the difference between inserts vs sends and when to use each.
The Difference Between Inserts and Sends
The best way of explaining the difference between inserts vs sends is that inserts are for one-off (only affecting one track) effects and sends are for effects you want to apply to multiple tracks.
Let’s talk about each one individually to better explain the difference between inserts vs sends.
To make it easier, we’ll talk about a specific effect for each (in this case reverb).
With an insert, we’re doing just that: we’re inserting an effect on the track itself as part of the processing chain.
Let’s say you have a vocal part in which a note is held. You want to tease that part, so you duplicated that track, reversed it, and placed it right before the actual part. The result is a nice fade in to lead into the actual part.
It’s missing something, though, so you want to send it deeper into the back in the stereo field with your reverb plugin of choice.
You dial up the size of the room and set the wetness to about 75% (maybe automating it down to roughly 0%) once it ends to simulate the sensation of it getting closer to the listener.
This is a very specific aesthetic you only want to create on this one part, so it’s best used by dropping it on the actual track as an insert.
Also important to note is that the wetness in this case should be set to whatever you want in this specific example. Using this effect as an insert is perfect for automating that wetness level, as well, as we don’t have to worry about its effect on any other tracks since it’s only affecting this one.
With a send, we’re creating a special track called an “Aux” or “Return” track (depending on the DAW, they’re the same concept, though). We then drop our effect on this Aux/Return track and use the Send knob or dial to blend in the amount of that effect that we want on a track by track basis.
Let’s say that you’re pretty far into the greater mixing process on the entire song, but it’s still feeling flat.
You decide that you want to give your entire mix a bit more personality. Nothing against your bedroom where you recorded everything, but its acoustics don’t exactly sound like Abbey Road (speaking of which, check out my tutorial on the Abbey Road Reverb Trick).
A bit of depth and color from a reverb plugin would serve the mix nicely, but you want everything to sound like it was recorded in the same space. Very important is that you ALSO want to be able to adjust how much of that depth each track gets.
In this case, you would create a Return track and place the reverb on that track. You decide on the room size you want (other parameters) and you’re good to go. The last thing you do is set the wetness at 100%.
When using an effect on a Return track for Sends/Returns, always set the wetness to 100%.
This is because we are using the send knob to mix in as much of that effect as we want alongside the clean. In this case, the send knob on the individual track is essentially the wetness because it’s turning up as much of the “wet” version of that track as we want alongside the clean that is the individual track.
Not only does the Sends/Return method create a cohesive sense because again everything sounds as if it was recorded in the same space, but it saves your computer CPU usage (see how to save CPU in mixing) and saves you time of having to put the same plugin on every single track you want to use it for in your mix.
Inserts and Sends Compared
To review or the TL/DR if you prefer – inserts vs sends have two distinct applications:
Insert – Use an effect as an insert, meaning on the actual track you want to affect, when you only want that effect on one track for a specific purpose. Set the wetness wherever you want it in this case.
Sends – Create a return track for sends/returns and place the effect on that track when you want to apply it to multiple tracks. This saves you CPU usage and time, plus it creates a uniform sense across your mix as the same specific effect is being applied to multiple tracks (albeit at different amounts). Lastly, set the wetness to 100% on the plugin (when applicable) in this case to get the full effect of the plugin, dialing up the send knob to taste which acts as a wetness for that specific track.