Let’s talk about using sends to control effects, parallel processing and some of the other benefits of sends.
First we need to understand a few concepts. Buses, auxes and sends.
What is a Bus?
A bus is an audio pathway that allows you to move a sound from one part of the mixer to another. The main outputs of your mixer is a bus, often called the Master Bus. Busses are very useful for mixing.
What is an Aux?
An aux is essentially the output of the bus. You use them to make subgroups or sub mixes, like all the drum tracks controlled with one fader, and also for anytime you want to do parallel processing. Often this is called an effects return.
What is a Send?
A send splits the audio signal and ‘sends’ it somewhere else, usually through a bus, but can also be to a interface output.
The entrance to a bus is by assigning the output of the track in a virtual mixer or by using sends.
Simple Signal Flow
Lets take a typical signal path in a mix.
A vocal track has it’s output set to your master bus. Simultaneously using a send it is being sent through a bus into an aux track with a reverb plugin.
You could put the reverb plugin as an insert right on that vocal track, but it’s really not the most efficient way of working. The reason it’s not efficient is because the reverb can not be shared by any other tracks. Using the reverb on an aux and using sends allows the most flexibility and only takes 1 plugin.
Advanced Signal Flow
Lets set it up for a drum mix.
Here I have a bunch of drum tracks, a mono overhead, a kick sample, a subkick, snare top and bottom, high and low toms and a ride cymbal.
The outputs of each of these tracks are set to bus 1 and 2.
By creating an aux track and setting the input to bus 1 and 2 I can now hear all the drums and control the overall drum mix level with just the fader on the aux track.
Listen to it: dry-drums
It’s pretty dry still right now and I’d like to add some reverb. I want reverb on the overhead, 2 snare tracks, and the 2 tom tracks. One option to do this is to open up 5 reverb plugins and adjust the wet/dry mix control to get the desired amount of reverb for each drum.
Listen to it: drums-with-verb-inserts
Reverb plugins take up quite a lot of cpu and I’ve already got 5 for just the drums and it doesn’t even sound that good. There’s got to be a better way.
Well there is and that’s by using sends.
Now I’ll get rid of those 5 reverb plugins and on each of those tracks make a send to bus 3 and 4.
I’ll make a new stereo aux track, set the input to bus 3-4, and open up a good reverb plugin like TL Space.
To control the level of reverb for each drum I keep the wet/dry mix on the plugin to 100% wet and adjust the sends on each track to add reverb.
Listen to it: drums-with-verb-send
Once it’s set up its a lot easier to manage and uses far less processing power, I can even share this reverb with the other instruments.
Next lets do some parallel compression on these drums.
I’ll make a new stereo bus and set the input to bus 5-6 and insert a compressor.
On my drum tracks I’ll make a send to bus 5-6 and bring up the level to about -10.
I’m going to set up my compressor for lots of high ratio compression. And adjust the level of the aux track to mix it in with the clean drum tracks.
Listen to it: drums-compressed
What else can we do with sends.
How about to set up a different headphone mix for each musician.
To set this up really easily just make create a stereo send on every track in your session going to analog output 3 and 4. You need a headphone mixer to actually get this mix to the musicians. The good news is there are plenty of low cost options for that from Presonus, and Samson.
With all the send faders at unity gain they will hear the same mix you hear in the control room. You can lower the faders to customize the mix. Or by setting the sends to be pre-fader you can have even more control. Pre-Fader means that the level going out of the send is not effected by the fader, mute or solo buttons on the track. This is great when you want to isolate a single instrument in the control room with out interrupting the performance.
(This article is from The Home Recording Show Podcast Episode 7)
Any questions?
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I’m on a commenting spree here haha
All hail!
I’ll be linking to this post…
How did you get pro-tools to display the faders in the sends and return tabs on the mix window? As in the “signalflow2″ picture
Hi Amir, the default view for sends is called “assignments”. If you ctrl+click (command+click) on the send selector you can choose to view one send at a time on a small fader.
I’m not usually using more than 2 sends on a track at once so this works great for me.
These are really great articles! One could only wish they had such concise info when they were first learning about buses and such. I mean, I still learned something about them just then, even.
absolutely great tutorial!