Audiotent Tip 346. Lo-fi Vocals.
When working on a clean and polished production, try making your vocals lo-fi for a contrast. There are multiple ways to achieve this effect.
First, equalise your sound, cut the highs and lows. Next, try adding a touch of distortion or bit reduction.
Alternatively, run the sound via guitar stomp boxes or amp effects. This should make your vocals sit better in a clean mix.