I've been reading snippets about all of Prince's Personal Cassette Players he had and used to record music. It sounds like he was recording all the time, at all hours and I can imagine he was using some high end units like the Marantz PMD 430 or maybe a Sony WM D6 although the article mentions a mono unit. These un-named units have been mentioned in a few other local articles and here's another one, the full article is in the link. http://www.startribune.com/c-j-ther...ormer-engineer-who-has-heard-songs/487824511/ "Q: Was Prince one of those people with a tape recorder next to his bed so he could put ideas in the recorder or did he go straight into the studio? A: A little bit of both. He had, lots of us had them because they were really popular, these little boom boxes. They were really cute. They were different pastel colors. His was a pastel purple, mine was mint green. He was popping in cassettes all the time because it also had a built-in microphone. A little mono mike. [Laughs] There have been some really poor-quality recordings floating around and some of them he did himself when no one else was around because we all had to sleep sometime. He’d set up that boom box on the piano, put in a fresh cassette and then just try out different ideas. A perfect example would be the song “The Ballad of Dorothy Parker.” He was asleep, he had this funny dream and he called me. He wanted get this song down as fast as possible. That was typical."
A little unrelated but a nice article about Prince's Pre-recorded Cassettes from our local public access radio station 89.3 The Current https://blog.thecurrent.org/2016/08/the-joys-of-prince-on-cassette/
The word Pastel immediately made me think of these Sharps http://mirror80.com/2015/05/80s-flashback-sharp-goes-pastel/ There were similarly styled mono units as well. In the comments someone says they had a Lavender coloured QT5. Presumably like this https://www.google.co.uk/search?q=s...&bih=722#imgrc=tmX2x13gTuhSqM:&spf=1531504077 You would have no problems making a poor quality recording with one of those. However, at that point it is the tune and lyrics that is the important thing.
I'll have to do the Paisley Park Studio Tour and see if there's anything interesting. I was thinking Sharp as well and seeing the purple one in your ad makes it more believable. Prince had a home by the studio that he painted purple, he had a very strong attraction to the color.