Admittedly, Signify is the only Porcupine Tree album I've heard. If it's any indicator of the quality of their other albums, there is definitely some hard earned money to be spent. Porcupine Tree purvey an somber variety of art rock, alternating between haunting gloom and murky dissonance within rather linear rock numbers.
Porcupine tree can be very complex, but also very subdued when minimalism is required.
Lush mellotron ambiance fills the gaps in the album's flowing stream of aural highs and lows, bathing the listener in strangely comforting darkness. The guitar lines are spacious affairs, threads of swirling reverb and cackling feedback. The guitars leave ample room between the notes for dark synth lines, subtle acoustics and vocal dynamism. He deftly moves between vaguely North African beats and beautifully syncopated Latin American dance without missing a beat. The vocalist and guitarist Steve Wilson has a voice seemingly designed for the haunting music - he can soothe with a warm, deep tone or send shivers down one's spine with a foreboding high wail.