For example, if guitar is another major melodic instrument in the piece, try spreading the guitar from left of center to center, and the keyboard from center to right of center. When a delayed sound is placed in the same spatial location as the main sound, the end result may become somewhat indistinct if the echoes are on the same note that's currently playing. If you're using stereo delay on a lead instrument that's panned to center, you can get some lovely results by panning one channel of echo toward the left, and one toward the right. If the echoes are polyrhythmic, this can also give some lively ping-pong type effects. One way to pan is just to arbitrarily move panpots around until things sound good.
Closer sounds are louder and drier.
You can also experiment with adding predelay to the reverb for a sound that you want to seem close to the listener. This works best when each of the main sounds has its own reverb. When Mono Matters There are three reasons to pay attention to mono. Another is that some methods that create stereo from mono signals, or ultra-wide signals from stereo, can create mono incompatibility problems. Don't do any stereo panning until you've used basic EQ with all instruments to make sure that each part stakes out its own part of the frequency spectrum.