I have the original Jazz and love it. Have had zero problems with mine.
Meadow: a mechanical machine is just that. There is no computer. You set stitch length, width, etc. by hand. Choose your stitch pattern by hand.Think of the older/vintage machines that have no computers; they are all "mechanical" machines. If you go to the Baby Lock website and put in Jazz or Jazz II, you will see a photo of the actual machine. Hope this explains it.