One more little update. I suspected the three tape machines were based on real world versions, but I had to do some more reading to discover what they represent.

So for the curious...

Fixed Head Mode - Based on the concept of a reel to reel tape deck being used as a delay.
Multi Head Mode - Based on units like the Roland Space Echo.
Single Head - Based on the Echoplex style decks.

The Spring Reverb was included likely because the Roland RE-201 Space Echo and the Fender Electronic Echo Chamber both had spring reverb tanks in them.

Anyway, it's time to go see what noises it can make tonight when I introduce it to Mr Flanger and Mr Tremolo, and maybe even Mr Chaos Theory (my FSH-1)...