In 1955, the Radio Italiana (Rai) established the Studio di Fonologia Musicale at RAI Center in Corso Sempione 27, Milan (Italy). Physicist Dr. Alfredo Lietti builded the famous “nine oscillators”, the white noise generator, the amplitude selector, the dynamic modulator, the ring modulators, the frequency shifter, the pulse modulator, the electronic fader, the “toc” generator, the cathodic comparer, the octave filters and the third octave filters.
Almost half a century later, the museum of Musical Instruments in the Castello Sforzesco now houses the equipment on which Luciano Berio and Bruno Maderna conducted the first experiments in electronic music.
An innovative digital library service allows the public to obtain informations and to listen to short excerpts from the rich archive of compositions carried out in such machines.
Maddalena Novati found about 400 tapes for 200 hours of listening, which she has been cataloguing, restoring and converting with the help of Laboratorio MIRAGE (Università di Udine) and Laboratorio Audio Rai (Milan).
I suggest you the following reading: "Technology and Technics: Alfredo Lietti and Marino Zuccheri", written by Giovanni Belletti [pdf].
Some excerpts from original footage:
[RAI Studio of Musical Phonology: historical footage #1]
[RAI Studio of Musical Phonology: historical footage #2]