Two hi-hat sounds worth comparing
Compare tip and shoulder strokes with the cymbals closed, then try a small opening.
Keep the hi-hat closed and play a few quiet eighth notes with the tip of the stick on the top cymbal. Then try a gentle shoulder stroke near the edge, with a glancing motion rather than driving straight through it. Listen for the difference in definition and wash.
Keep the tempo and volume as consistent as you can. Moving the stroke and opening the cymbals together makes it difficult to hear which change produced the sound. After comparing the closed sounds, repeat the tip pattern with a small opening and listen again.
Your cymbals, foot pressure, and stroke all affect the result. Choose one sound for a passage and try it with the band. Listen for whether the hi-hat stays clear without covering the vocal, and adjust your stroke or foot pressure before repeating the passage.