Harmonic exciters are great tools, sometimes you want to use them drastically, and sometimes very minimally (Especially in mastering.) A great trick is to put a harmonic exciter on a send, set it up, and turn up the send/return a few clicks and adjust to taste ;)
It's great to have stereo instruments in your song, it's also important to have mono instruments or less stereo based instruments as well because it will give a sense of contrast and make the stereo instruments sound even wider!!
The label I am apart of just released a free sample pack, here's the soundcloud demo featuring three of our artists. I recommend checking it out, especially if you make wave or phonk music, since that's what they were geared towards.
Always check your mixdowns and masters in mono, I usually check before I mix/master and after I mix/master as well as after doing any drastic change throughout the process (especially if it involves heavy eq or stereo/panning. I will give you a few reasons you want to do this, everyone wants a wide and interesting mixdown, but most of the people hearing your song are going to hear it in mono. Also when you play it in the club it'll be playing in mono usually.
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