A correspondent e-mails to say that he first discovered the sound mirrors when he saw pictures on the CD booklet/cover art of a Bass Communion album.
They are great images, done by Carl Glover of Aleph Studios, showing a view up the 200 foot mirror at Denge.
Bass Communion is a project by Steven Wilson, leader of the band Porcupine Tree. According to the Bass Communion website, it specialises in
recordings in an ambient and/or electronic vein, sometimes in collaboration with other artists. Most of the pieces are experiments in texture made from processing recordings of real instruments and field recordings.
The March 2003 album Bass Communion (remixed) contains
Reconstructions and recycling of Bass Communion music by artists from the experimental, electronic and ambient music scenes.