I update here a mail I wrote in 1997:
Thomas Diethelm is a Swiss nylon guitar virtuoso that made some success in Europe mid 80ies using a unique kind of LiveLooping:
He was rather of the individual kind, had his own strong style (literaly, he was a champion in spear throwing, before dedicating to the guitar!), a virtuoso as long as playing his own compositions and using his AMS DMX 15-80S digital delay and pitch
He wanted to live on his music and tried to be popular. He used to say that he needs to create 'liedli', little songs - as opposed to the instrumental compositions he would naturally create. Its a pity he neither made the big success he would deserve for his ability nor do we have the music that really came to him... but its still very amazing and unique what he left us!
His main technique was to set up a pattern of delayed pitch transpositions.
So each note he played turned into a short melody of 2 to 6 notes. For each
song, he used specific patterns and composed using the delayed transposed
This may sounds trivial, but once you listen to his records (about 6 of
them, “Valeys in my Head" I would recommend most) you get impressed how far
he went with this technique.
>From this album on he also used a Paradis Hexaphonic guitar with Polydistortion effect he faded in to set accents.
Often he quickly alternated between chords and melody playing and due to the
delay both were constantely present and due to the
pitch shift, there was no impression of repetition. The limitation of this
technique made him creative in terms of composition and gave his own sound.
Two of the records he made in team with one of the best Swiss keyboarders
Santino Famulari, the others feature an always changing good band. only the last album is almost solo I heard him often play solo when we worked and always found it sounded much more impressive than with the band.
He complained a lot about the failing (bad contacts) expensive and sensible AMS studio
machine. since he completely depended on it, this might even have contributed to the end
of his career around 1990.
For 10 years he was happy to sells dried spiced fish (he was a brilliant cook, too!).
around 2005 someone created a special MAX software on a WinXP Laptop and he tried a comback with the last recording Guiteros.
then he lost his workshop and living place and had to sell his instruments and lost the reason to live and died in 2013 rather miserable.