1978’s Pyramid was a conscious attempt to create a signature sound from the various strands of the first two Alan Parsons albums, Tales Of Mystery And Imagination and I Robot.
Much of that sound came from the innovative use of orchestra and choir by arranger Andrew Powell that provided a colourful backdrop for Eric Woolfson’s songs and the variety of vocalists that were brought in to sing them – Colin Blunstone, John Miles, Dean Ford (from the Marmalade) and Lenny Zakatek. The result was a strong, cohesive album, despite the presence of so many different singers and the fact that Woolfson’s songs are not among his best.
The Alan Parsons Project – Pyramid, Super Deluxe Box Set – YouTube 
Meanwhile, Parsons’ production is good enough to withstand the remixing and remastering it gets on CD and vinyl, and the surround sound mix it gets on the Blu-ray disc.
The real treasure trove for prog fans are the 67 bonus tracks – all but 14 previously unreleased – that meticulously unravel the album’s complexities and trace them back to Woolfson’s original demos. The 14-minute track of Colin Blunstone trying different treatments on The Eagle Will Rise Again while maintaining his own vocal character is a real revelation.