Box office Its performance at the box office was disappointing.
Critical The Monthly Film Bulletin wrote: "Another Hammer horror, and within its own terms quite a spirited offering. Given a plot somewhere between
Fanatic and
Taste of Fear director Alan Gibson has injected a gratuitous amount of sex into the story but otherwise presents the usual mixture with a sure style and a good eye for colour. The dream sequences – like Georges' nightmarish premonition that his insane brother will eventually kill him – are particularly effective. The dialogue does creak somewhat, but the next Hammer surprise is never very far away: even the butler turns out to have been a frequent inmate of asylums, though he seems about as normal as anyone else in the film. Jane Lapotaire overacts rather gratingly as the maid, but Margaretta Scott moves from sanity to insanity with gracious ease, and Stephanie Powers is an attractive heroine, though the thesis never gets very far."
The Radio Times Guide to Films gave the film 3/5 stars, writing: "This "mini-Hitchcock" thriller from Hammer Films borrows as much from
Psycho as it does from the studio's own series of early 1960s whodunnits (
Paranoiac, for example). Touted as a new departure for the "House of Horror", this demented tale of dead composers, lunatic twins and drug-addicted cripples merely adds sex and discreet nudity to the tried-and-tested shocker formula. If you can swallow Stefanie Powers as a PhD music student, this one's for you."
Leslie Halliwell wrote "Lunatic Hammer horror with the courage of its shameless borrowings from
Taste of Fear,
Fanatic,
Nightmare,
Maniac and all the films about mad twin brothers, to which this chaotic brew adds dollops of sex and heroin addiction." In
Hammer Films: An Exhaustive Filmography, Johnson and Del Vecchio wrote: "Not much could have improved
Crescendo, which was critically injured from its inception. It had all been done before, and better." == Home media ==