Fabian Müllers writes the following in the booklet of his CD “Passionato”, recorded on the “353018”:
"My thanks go to Johannes Kammann for his great and always patient work as sound engineer, to Stefan Knüpfer for his magical abilities to make the piano sound the way it does and especially to Annemarie Schindler, who made her wonderful 1956 Steinway grand piano available to me for the recording; the warm and richly coloured sound of this instrument inspired me every second."