How to Clean up Cassette to Digital
Reply #16 – 2003-05-07 14:43:38
An MA-XG won't hurt. But in 2000, when I still recorded on cassettes, the MA had a case labeled "super precision anti resonance cassette mechanism" while the SA didn't. The flutter affecting the Bias 10 kHz calibration tone was indeed lower on the MA tapes. I can still measure it, if anyone needs it. ~~ Yes, but the problem is the lack of reference. It is easy to set the alignment right for a given tape, but how to set it back after this, in order to record new tapes ? The only reference I could find was pre-recorded tapes. And some of them had so weak a buffer that the tape was not properly pressed against the head. So be careful, if you turn half a revolution clockwise, remember to turn half a revolution counterclockwise after the recording. Having a reference for speed is easier, because TDK tapes display their lenght in meters. I then calculated, granted that the tape is 135 meters, and the speed 1+7/8 ips, that a 90 minutes TDK tape should run 47 minutes and 15 seconds per side. Exeeding the rated lenght allows them to guarantee 90 full minutes even on mistuned deck (the tolerance is +/- 2 % for consumer gear and +/- 0.5 % for professional gear, IIRC, or maybe there is a 1% in them...) ~~ Dolby C and S can be applied on recent tapes, granted the head is properly aligned. Old tapes loose treble, and the decoding process doesn't match the encoding process, so that the sound is "pumped" when dolby is set on playback as well as on record. Playing an old Dolby tape without Dolby doesn't harm much. It even helps to recover some of the lost treble. Dolby B is very sensitive to this problem. Hmmm ... AFAIK, the TDK SA showed that SPAR-casing, too (at least until 1996 when I stopped using Compact Cassettes as a medium) ... might be that TDK removed the original SPAR-casing from the SA series for price reasons, though. TDK SA-X and MA-X had a casing named SPAR-II which was believed to be even better when measuring flutter and overall phase stablility ... ~~ When it comes to aligning the heads, a useful method is to record a perfecly correlating (L=-R) white or pink noise (can be created via cool edit and then be burned to CD) to a good and phase stable cassette before screwing the playback head for a specific recording ... for switching back to the old position, simply play the tape, put the amp to monaural output and you will hear high frequencies on a misaligned deck ... now turn the screwdriver until the high frequencies are no longer heard ... this is the position in which the reference tape has been recorded before. ~~ IIRC, dolby circuitry needs a perfecly calibrated tapedeck as well to work correctly (calibration is 10k BIAS and record level @ 315 Hz) ... if you play a tape that has been recorded with dolby and switch dolby off, you will hear more treble but less bass (due to compression during recording) ... remember to take care of this by using a parametric EQ afterwards ... When it comes to "pumping" sounds (most likely on old cassette tapes), it definitely is better to switch dolby off completely ...