If the first album was spare, Blood is a tour de force of both production and vocal expression. There are echo effects on many of the interior monologues and telepathic passages, dramatic amplifications and fades, 1950s-style "vibro" sounds, megaphone filter effects, and a heartbeat under the narrative as Jack slays Emily Matthews.
Ellison wisely lets the producers do most of the work for him; his delivery is understated, less conversational, more antiseptic -- as befits the material. You can just hear the creepy lilt in "and he smiled," the gentlest sniff of distaste in "how hideous" (the thought that he had eaten Kate Eddowes's kidney), a slight pause of nausea in "that filth, she had actually kissed him," and the drop to a whisper on the final word of "He was not evil, he was pathetic."
The only obvious vocal pyrotechnics are his fine inflections: Hernon's avuncular grandfather-who-is-not-old, the haggish gardenia Van Cleef, Rose the rose as a New England housewife, Cashio the phlox as a grizzled gentleman, Nosy Verlag the wild celandine as a snippy queen, and the Cockney of Jack's letter to the authorities, a more gentle version from his mouth in the flashback to Spitalfields, and the heavy, cooing street whore accents of Emily Matthews.
This is about as good as it gets.
(Originally, this was a double LP with two sides of Robert Bloch reading two of his spooky Ripper stories in a cheerful, grandfatherly voice. They also have mostly unintrusive musical backing, although a goofy organ opens "A Toy for Juliette," and playing "Rockabye baby" beneath the climax seems to me hamfisted and in questionable taste. Perhaps significantly, no one is credited. The Ellison story is apparently available alone on cassette from the Harlan Ellison Recording Collection.)