The continuous noise filter is great for removing tape hiss. The best way to filter tape hiss is to sample a portion of the track which contains only hiss, and no music. Sometimes this is not possible, however, and that's where these presets can be handy.
I use these as starting points. They are simple curves with a small "hump" in the region where hiss is found. The "DeHiss" versions are the same curve at different thresholds, and the others have a rise at the bottom end to filter some low-frequency noise as well.
The attack times are very short. I've found this necessary to keep the filter from "biting off" the first note. The release times are fairly small also. I often increase the release time if the sound gets a bit hollow. Increasing the FFT size to 4096 can be helpful also. I seldom change the attenuation; it usually works well set to a small amount. I decide on using the smoothing feature on a case by case basis... I've found it helps sometimes, and hurts others.
I've also included a de-hiss preset for the dynamic noise filter. The continuous filter usually does a better job, but on occasion the results from the dynamic filter sound better. As with the others, this preset is a starting point; I determine the best settings by previewing and adjusting.
The names have "~JH" at the ends... I do this to make them distinguishable from the ones provided with the program.
I hope they are helpful.