H.-W. Schmitz was able to track down the Lipp recording grand piano (serial number 26087, photo from DMM 040) at the time. Unfortunately, the recording technology had been removed decades before. What had survived, however, were the many signatures of the pianists who made recordings for DUCA. We compared the dates in the DUCA music catalog with the dates found next to the pianists’ signatures on the grand piano’s frame. The vast majority of the dates correspond exactly to the recording date in the DUCA book. Some dates are a few days before or after the recording date according to the DUCA book. We assume that the pianists were usually in Frankfurt for several days and in some cases also accompanied the preparation and post-processing of the roll recordings or approved finished master rolls.