Taste of Cinema, in their infinite wisdom, has ranked the Phantasm score among the thirty greatest horror soundtracks of all time. Fred Myrow and Malcolm Seagrave's memorable musical accompaniment clocks in at number twenty-six on their list, which is split into four parts. Phantasm is sandwiched in between Zombie Flesh Eaters and Alien, the latter you'll recall being another 1979 flick with a yellow-blooded alien in it.
They write, "This soundtrack sounds like it was made in a mausoleum at midnight." Such a fitting description! Hit up their website at the link above to read what else they have to say about the Phantasm score and to see what other horror film soundtracks made the list.