Interesting. I make a system that allows contact with spirits/entities and don't get sounds of hell, even though some of the contacts can be somewhat negative sounding, and threatening. I have a site to share information
http://franksumption.tripod.com/

There does seem to be faction out there in the nether world that would try to scare off would be researchers, and can sound demonic, and threatening, but it's been my expereince that it's only a paper tiger. I've been doing this work for six years now, and have always found it intriguing, and fasinating, but never harmful.

Frank