Have you ever been working on your mix and a certain element just won't fit? Despite your best efforts, with gain staging, EQ, compression, phase-correction, or other effects, a certain sound falls out of the mix. What's the best course of action when all else fails? The answer is simple, change the element(s) that is/are causing the problem. One cleaver function in Ableton makes changing a given sound almost painless, this function is called "Hotswap."
Hotswap works by switching a given sample, instrument or effect preset for another. Look for the little Hotswap icon, click on it and instantly Ableton's browser will open the directory in which you found the preset or sample. From here navigate the browser window and double click on any sound to swap it in. Just like that you can change out a sound for another in realtime in the context of your song. The video below shows how you can use Hotswap.
Hotswap is something I use all the time. It allows me to work quickly. As I've said before, working quickly is the key to executing creative ideas i.e. finishing songs. Nothing kills you're creativity like stopping mid-composition to EQ a kick drum for 45 min. Forget the effects, the 'right' sound will pop without any EQ, compression or effects. If the sound you're using doesn't sound good without extensive massaging, it's the wrong sound. Pick another one (you're not married to it), put it in your song (use Hotswap) and move on with your life.
The idea of a sound being the right sound is sort of subjective. But there are a few questions you can ask yourself to help guide your sound selection.
1. Can you hear it?
If you can't hear a certain sound and it falls out of the mix, try altering the phase of the sound. If that doesn't make it pop. Swap it.
2. Are there other sounds occupying the same 'space' in your song?
I consider a song to be a three dimensional room. When you make a mix every element needs to have it's own space in that room. The three dimensions are: volume, front of the room (louder) to the back of the room (quieter); panning, left and right; and frequency, up (high frequencies) and low (low frequencies). Maybe your kick and sub take up the same space in the mix. Change them. Place your sub lower and bring your kick up higher (or viceversa). Is your lead hard to hear? Try increasing the MIDI notes by an octave. Vocals and guitar are in the same place? Pan them to opposite sides of the room. Get the picture?
3. Is it too similar to other sounds in your mix?
What makes two element sonically resolve from one another in the mix is determined by how different the sounds are from each other. Use sounds from different sources, i.e. vinyl sample vs digital sample, software synth vs hardware synth, Massive vs an other synth (lol).