Nakamichi is the best designer of cassette decks in Japan, and its success is global, with products that are still absolute references in cassette playback.

The Nakamichi RX-505 perfectly illustrates the company's taste for originality. In addition to incorporating fully separate recording and playback heads, a closed-loop double capstan, and Dolby-B and Dolby-C noise reduction systems, the RX-505 is a unidirectional cassette player with a spectacular automatic reverse function.

This last sentence may seem contradictory, as other automatic reverse decks move the tape bidirectionally, first in one direction and then in the other. To play the reverse side of a cassette on a classic unidirectional deck, you must manually remove the cassette, turn it over, and reinsert it into the machine.

The RX-505 automates this manual process. When you press the eject/load button, a module inside the deck slides forward by more than 5 cm, revealing a support into which the cassette is inserted, label side up. When you press the button again, the module is pulled back into the machine, where spring-loaded arms engage to ensure the cassette is properly positioned.

This approach to the automatic reverse function is based on sound reasoning. Maintaining a constant frequency response at 20,000 Hz at a tape speed of 1-7/8 ips (a Nakamichi characteristic) requires exceptional azimuth alignment. (Perfect azimuth alignment is achieved when the magnetic gap of the playback head is perfectly perpendicular to the edge of the tape.) With any cassette player, an azimuth error of just one-sixth of a degree will result in a 10.25 dB loss at 20,000 Hz.

Many factors – the alignment of the capstans, the manufacturing tolerances of the rollers and tape guides inside the cassette compartment, and the precision of the tape cutting, to name just a few – influence the exact path of the tape and therefore the azimuth angle in a cassette system. Unless the tape deck is equipped with an automatic azimuth alignment system (such as the Nakamichi Dragon), the playback heads must be aligned constantly to balance these factors.

According to Nakamichi's research, however, this balance is not preserved during reverse playback. (In a conventional automatic reverse deck, for example, a completely different capstan is used for reverse playback.) The additional azimuth error produced by conventional bidirectional operation may be small enough to be tolerable on decks not aiming for a uniform response at 20,000 Hz (or higher).

An exceptional cassette deck with high-quality sound performance.