When I select the Hulda Clark full spectrum sweep preset, I notice in settings that the amplitude is set at 2 volts. Should I be running this preset at 20 volts?

Spooky2 is still heavily about experimentation and there is still to be any determined any right or wrong settings.

In the case of the HC spectrum sweep, Walt believes that lower voltages are better and are more effective when communicating via DNA; his preset splits that 2V between 96 child frequencies so there is actually only 0.02V being applied per frequency! The theory is that its about what is being communicated and not how loud; in fact too loud may be counter-productive.

Presets with 20V followed a different line of reasoning that 'more is better if I want it to resonate' and this setting will shake things around more.

My experience with dealing quickly with symptoms is to use amplitudes in-between these two extremes. 20V can make a rapid change, but it soon can become too much for some people. Low voltages (<2V) appear to be very effective for around 12-24 hrs but then seem to lose effectiveness; after a break they become effective again. 2V can be run for months at a time without causing issues. 4V is good if you want the preset to have a bit more strength, weeks at a time. In many cases it comes down to the individual - beyond all of these amplitude settings; it is more important in the first-case to be running the right frequency.

If you would rather use 20V than 2V you can change the preset; and save it to your user folder.

For more details, please check the link:
https://www.spooky2.com/forums/viewtopic.php?f=5&t=7813