At the time of their LP recording Fonetiks (BEAD 24), both Chris Burn and John Butcher were both working with electro acoustic techniques. John Butcher was placing a microphone inside the bell of his Saxophone, with both the amplified sound and controlled feedback.
Chris Burn was also using a microphone , in his case hand held and moved over vibrating percussion instruments - primarily cymbals and gongs - and the strings of the piano. (A technique similar to that which Stockhausen used in Microphonie 1.)Chris Burn pursued this technique for only a short while and electro acoustics disappeared from his work for about ten years; though he continued to use a variety of percussion instruments placed in and around the piano. Part of the reason for moving away from electro acoustic methods may have been that many of his acoustic techniques resulted in sounds with a strong kinship to those produced by electronic means:
It is tempting to get into technical explication notating Music for Three Rivers - to talk about how Burn makes which sounds, the details of each preparation, etc. For instance, what does he do to produce the utterly confounding note bending on "The December Light" and "Tall Wind Dragging"? (Pitch- Shifting, like putting the piano through a Leslie speaker; frankly I have no idea how he does it.)John Corbett
In the early '90s he began to amplify sympathetic resonances produced by silently depressing keys and hammering others. He also investigated the possibility of experiencing difference and summation tones as part of the piano's sound world. Examples of the above can be heard on Music for Three Rivers 1997(Victo50), somethingtobesaid (John Butcher Group 2008 WOW2) and more recently on the 2009 recording for Another Timbre, 'the middle distance'. (at24).
Complimenting his use of amplified sounds, Burn had begun to introduce electronic treatments of the acoustic piano sound into his work. Following some initial London concerts that incorporated these techniques, (Red Rose Theatre, The Vortex,) he used amplified techniques and electronics in sections of his solo concerts in Munich and Ulrichsberg, (both in 2007); and continues to do so to this day, most notably at Concepts of Doing Festival, Berlin 2013.