Here's the uncomfortable truth from a site whose whole business is removing hiss: most hiss is self-inflicted, and preventing it takes less effort than removing it. The villain has a boring name — gain staging — and understanding it takes one paragraph.
Every recording chain adds a faint electronic whisper: the mic's own electronics, the preamp, the converter. That whisper sits at a fixed, tiny level. If your voice is recorded loud relative to it, nobody ever hears the whisper. If your voice is recorded quietly and you turn everything up afterwards — in an editor, or with a normalizer — you turn the whisper up by exactly the same amount. The hiss was always there. You amplified it into the spotlight.
1 – Get close. Halving your distance to the mic roughly doubles your recorded level without touching a single setting — the cheapest gain in audio. Two fists from mouth to phone is the working rule.
2 – Set level off your loudest sentence, not your average. Speak your loudest likely line; the meter should peak comfortably high without hitting the top (clipping is the one sin worse than hiss — hiss is removable, distortion isn't). Then leave the level alone.
3 – Kill the noise you can hear. The fan, the fridge, the AC vent above you. Every one of those becomes "hiss-like residue" later. Thirty seconds of switching things off outperforms any algorithm, ours included.
Cheap built-in laptop mics hiss at any level — the electronics are just noisy. Old cassette and field recordings carry tape hiss you inherited, not caused. Wind is its own category (no spectral tool fixes wind rumble; a foam cover or a repositioned phone does). For all of these, the noise remover is the right tool and earns its keep — you gave it steady noise, which is exactly what it eats.
The pattern worth keeping: prevention handles the noise you make; removal handles the noise you're given. Doing step 1–3 above means the tool becomes your occasional rescue, not your routine — which, from the tool's perspective, is how it should be.