Konstantins Raudive (1909–1974) was a Latvian born psychologist who was also an avid researcher of parapsychology. And he also had a great belief in life after death and the continuation of consciousness. He investigated with Hans Bender the subject of EVP, and published a book in 1971 entitled Breaakthrough: An Amazing Experiment in Electronic Communication With the Dead. He also worked with Friedrich Jürgenson in his attempts to capture EVP. It is said that he taped approximately 100,000 audio tapes claimed to contain EVP snippets. These were all claimed to be done under strict laboratory conditions. Whether this is true to standard scientific criteria I cannot say.
