As for the quietness I noticed in the DAT tapes, the low noise level may have resulted from improved electronics in the DAT recorder. Sony has pioneered Japanese efforts to create improved circuits in the section of DAT recorders in which digital signals are converted back to analog form. In many listening comparisons, I found the noise level in the DAT tapes quite a bit lower than the noise in most CDs. What noise I could detect was smoother, too. Finally, the tiny DAT tapes are far easier to use than the bulky videotapes used with standard digital recording systems.
Index marks recorded on the tape let the machine know where each selection begins.
In other respects, the little Sony behaved just like a regular portable cassette machine. It was much more resistant to vibration than my Panasonic cassette recorder, but otherwise it was so similar that anyone who's ever used a dictation machine would have no trouble using the Sony DAT straight out of the box. The battery is rated for two hours of use before needing recharging. Not on your life. Right now, DAT is a toy for rich consumers, although it's a promising new development for professional recording engineers.