Normally, some tradeoff is required to get auto-reverse convenience-though, in fairness, most reversing decks we've tested sell for less than half of this one's price. Superficially, this is not too different from the head arrangement in some other decks we have tested with bidirectional playback actually, the automatic azimuth adjustment, added to the inherently flat, wide-band response that is a Nakamichi hallmark, makes the Dragon the first automatic-reverse model we have tested for which no performance apology need be made. There are three heads: erase, recording (for the forward direction only), and playback (a four-track design, with a bifurcated right-channel gap for each direction). Nakamichi solves the problem with a quartz-lock system that keeps the takeup capstan running 0.2% faster than the supply capstan (for optimum tape tension and head contact) no matter which direction is in use. The use of different capstan diameters (and, therefore, rotation speeds), to prevent cumulative resonances in the two drive systems, complicates the issue. Furthermore, its direct-drive capstans must be used in two directions, whereas all previous Nakamichis have been unidirectional. The Dragon's closed-loop dual-capstan drive follows the design of Nakamichi's ZX-9, except that in Dragon, each capstan is individually driven by its own motor. We found many tapes in our collection that required azimuth adjustment away from the playback head's median position, but none whose azimuth was beyond NAAC's range. Its inventors call this feature NAAC, for Nakamichi Auto Azimuth Correction, and its range is broad enough to encompass azimuth disparities that, left uncorrected, would produce serious high-frequency rolloff, with response theoretically down by about 3 dB at 10 kHz and 10 dB at 17 kHz. (The direction indicator in use- forward or reverse-flashes until any ' 'perceived" error is corrected.) So the azimuth of any tape, no matter what its origin, can be matched by the adjustment process as long as the error falls within the Dragon's adjustment range (☑2 minutes of arc, or one-fifth of a degree).
The Dragon compares the signals coming from the two sections of the gap and automatically adjusts the playback head's azimuth until their phases exactly match. Its right-channel playback gaps (of which there are two-one for the forward and one for the reverse direction) are split, so that the inner and outer edges of the track are read separately.
Herein lies the Dragon's breakthrough: Instead of aligning its recording head to match the playback head's azimuth, it adjusts the playback head to match the azimuth of whatever tape is being played. (The current version of that model, the 1000ZXL, performs this task automatically before you start recording.) But alignment of the recording head does nothing to eliminate the disparities that can occur when you try to play a cassette that wasn't recorded on that particular deck. When Nakamichi introduced the first three-head cassette deck, the original Model 1000, it included a system that enabled the user to align the azimuth of the recording head to that of the playback head, so that every cassette made on the machine would play back on it with the highest possible accuracy.
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