When you’re mixing music there are two ways to affect the audio you are working with. Whatever your processor does there are two ways to make it work on a signal. Either by using it as a send effect, or as an insert.
But what’s the difference between the two?
What’s a send effect
Send effects are used when you have an original signal that you want to modulate, modify or process in any way without affecting the original signal. Your original signal sits there by itself unchanged but it has a separate copy being effected. You hear this with delays and reverbs; the original audio is there as well as the delayed signal working together to create a nice effect.
You use auxiliary sends to copy the original audio to a separate track where you further process it.
What’s an Insert?
An insert is used when you want to process a signal directly. You insert an effect, such as a compressor or EQ directly onto the original audio. This is when you do not want to retain the original audio file. You want to change it completely(or subtly) and only hear the processed part.
So when is it smarter to use sends or inserts?
Well, you want to use sends when you are using time based effects. Time based effects, such as delays need an original sound source to work. How would you know a signal was delayed if it didn’t have an original un-delayed track.
Inserts are used for processing directly. If you need to compress a signal, gate it to eliminate bleed or process it in any way that doesn’t affect the time of the signal.
Compressors are not time based, they are dynamic processors that work directly on a signal. That’s why you should usually use them as inserts. If you were to use a compressor as a send you wouldn’t be compressing the original signal, you would have a copy that’s compressed but it wouldn’t matter because your original is still unchanged.
Breaking the “Rules”
Of course, there are instances where you can break the rules. Using compression as a send is a well known trick. It even has a swanky name, The New York Compression Trick.
Mo Volans’ easy parallel compresison article on Audiotuts teaches you how to do a similar thing without using a send. You can just use the compressor as an insert as you normally would and then use the mix slider to apply the parallel compression.
Guitarist that use delays, reverbs and modulation effects in their signal chain are essentially using time based effects as inserts. But most guitar effects have a mix parameter to allow you to blend the two signals.
You can do the same thing with your DAW. For instance, if you have a guitar track you can usually insert modulation effects as an insert. Just be sure that you’re blending the two signals. You don’t want an insert to be 100% wet(or effected) since you won’t have any of the original signal.
It’s smart to use send effects when you want to enhance a signal without eliminating the original. By adding a delay to an already nice sounding signal you just make it sound better.
The opposite goes for inserts. Use insert effects when you want to change the signal completely. Inserts change the signal with dynamic changes like compressors, or tonal changes like EQ.
Both methods have their uses, and both are used for certain situations.
How are you breaking the rules lately?
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