you can split your signal into Mono vs Stereo or Left vs Right and EQ each separately. This can achieve a very cool stereo effect. When using Mid/Side EQ, try to increase the side signal to create a wider stereo image. We can use the same approach with a Left/Right stereo EQ by processing the left and right stereo channels independently.
Stereo Delay (2-10 ms)
Using a very short delay, anywhere between 2 and 10 milliseconds, will create a quick repeat on the side which can give the effect of width.
Two Panned Reverbs
On two empty return/aux channels, set up two reverbs. Pan one to the left and one to the right. Mess around with the different decay timings on each to manipulate the sound and it’s width.
Stereo Enhancement Plugins
Stereo Enhancement Plug-ins, like Bass Kleph’s Easy Stereo and Infected Mushrooms Wider do a great job at spreading the signal while maintaining the quality of the mono sound.
Parallel Distortion + FX
Parallel Distortion in general is a great way to add character to a sound. Send your signal to a bus with distortion. You can also put other effects after the distortion like widening plugins such as flangers, choruses, etc. But don’t forget to clean up the low end with an EQ.