I was in the second year of 6th Form when this album came out, and (unusually for a child of the 70s) I had only just discovered Genesis thanks to the 1978 Knebworth concert broadcast on Radio 1. Consequently I wasn't immediately aware that the band playing at Knebworth had something missing.
A bit like Voldemort's Horcruxes, Steve Hackett contained a little piece of the soul of Genesis, and in 1977 that piece broke off and went its own way. "Spectral Mornings" is Hackett's third solo album, and his second since leaving Genesis, and I remember at the time thinking that it sounded just like a Genesis album anyway. In particular the track "Clocks-The Angel of Mons", which alongside Hackett's haunting guitar, has what sounds like Phil Collins seriously going for it on the drums.
Of course it isn't, it's John Shearer, but it just goes to show how much of the Genesis "sound" was down to Steve's guitar. Although this was post-punk, Genesis however were still somewhat ponderous (the slimmed-down 80s pop version was still a few years away yet), but this album was anything but.
If you really need to label it, then it's definitely a "prog" album, but there are several different styles of music on show here, from Acoustic ("Lost Time in Cordoba") to Ragtime ("The Ballad of the Decomposing Man"). But if you simply want your Prog fix, Hackett's trademark guitar is all over tracks like "Tigermoth", "Spectral Mornings", "Every Day" and the aforementioned "Clocks". In fact the guitar solo on the track "Every Day" takes up the whole second half of this 6 minute song!