Steve_Graham@ub.cc.umich.edu (09/14/90)
I agree with Bill Vermillion and others about Dolby. Virtually every cassette deck I've encountered has not been well enough set up "off the shelf" to allow Dolby to track correctly. Dolby is trying to address this problem by specifying tolerances that have to be maintained by decks that will incorporate Dolby S. (By the way, all noise-reduction circuits DO have sounds of their own, just like other components. But usually they are worthwhile compromises if the music has wide dynamics, and I assume we are talking about grosser problems here.) I also agree generally with BV's lucid tape-deck setup instructions, with a couple of caveats. The amount of overbias at 10k is dependant on 1) the tape formulation, 2) the tape speed being used (not every reel user runs at 15ips) and 3) the head gap. The advantage to setting bias this way, as I see it, is that it is a highly repeatable setting. The low frequency method generally works well, but can give inconsistent results on some consumer decks, especially if the have narrow tracks. And on the other hand, I tried that with 3M decks once and was utterly confounded. Those decks have a transport that virtually stretches the tape over the heads, and there just wasn't enough modualtion noise for me to hear anything meaningful! The old standby method of adjusting for maximum output (or just past it) at 1 kHz will always get you in the ballpark, though it's a pretty rough adjustment by that method. My boss bought a portable Crown CD player (not Crown, the people who make big amps etc--some Japanese company). It didn't sound horrid, but there was considerably more IM distortion than most players have, and lots of low-level grunge, if memory serves. Eventually it started to skip at random. You are probably getting what you pay for with such things. --Steve Graham sg2@ub.cc.umich.edu USERHEFX@UMICHUB.BITNET