Nakamichi 682ZX: Visualizing the Perfect Waveform
Against a dark backdrop of vibrant, swirling neon oscilloscope lines—representing the chaotic beauty of pure sound waves—sits the monolithic Nakamichi 682ZX. This striking ad perfectly pairs abstract sonic energy with absolute mechanical precision.At a time when the industry struggled to get consistent performance out of cassette tape, the 682ZX smashed expectations with an incredible, flat frequency response of $20\text{--}22,000\text{ Hz } \pm 3\text{ dB}$. It achieved this studio-grade feat through an engineering tour-de-force: Nakamichi’s legendary discrete three-head technology, an asymmetrical dual-capstan transport that killed scrape-flutter, and a built-in 15 kHz test tone generator.But the real magic lay in its fully-automated azimuth alignment and level calibration. Because no two cassette shells were identical, the 682ZX actively corrected for tape housing imperfections on the fly. Enhanced by both Dolby B and C noise reduction, this deck didn't just record audio; it tamed the wildest frequencies, cementing Nakamichi as the undisputed leader in cassette recording history.
Asymmetrical Dual Capstans
Silent Mechanism
Diffused-Resonance Transport
Digital Fluorescent Display
Auto Azimuth Alignment
RAMM (Random Access Music Memory)
Double Capstan
Discrete 3-Head Technology
Pressure pad lifter
3 Heads
Dolby-C NR
Digital Meters
Full Logic Control
Metal Tape
Dual Capstan
Stereo
Rack Mountable
Embrace Analog Legend with the Nakamichi ZX-7
Ignite your audio soul with the Nakamichi ZX-7—the 1981 pinnacle of cassette mastery, a $1,250 icon that outshone nascent CDs and reels. This discrete three-head marvel enables off-tape monitoring, capturing every whisper with dual-capstan precision and diffused-resonance transport for flawless stability.Manual calibration—azimuth, bias, sensitivity, and EQ—tailors perfection to normal, chrome, or metal tapes, unlocking 20Hz-22kHz highs that rival vinyl's warmth. Dolby B/C noise reduction silences hiss, revealing lush dynamics and crystalline detail. Microprocessor logic, silent mechanism, and pressure-pad lifter ensure effortless operation. No compromises—just transcendent, tape-born bliss. Revive the era's glory; own the ZX-7 today!
Asymmetrical Dual Capstans
Silent Mechanism
Diffused-Resonance Transport
Microprocessor Control
Double Capstan
Discrete 3-Head Technology
Pressure pad lifter
3 Heads
Dolby-C NR
Digital Meters
Full Logic Control
Metal Tape
Dual Capstan
Stereo
The motor used in Sankyo transport decks is a major source of problems in these aging decks. The problem is seen as a deck that seems to not respond to front panel controls (play, stop, rewind, etc.) and on some decks where the transport mode lights flash after an attempted mode change. This is caused by a dead spot that has formed on the control motor stator. A short term fix is to open the deck and give the motor shaft a little nudge. This usually gets it out of that dead spot, but, it will get stuck again. Some people have had success with spraying Caig Labs, DeoxIT into the holes on the back of the motor and cycling the deck through the modes several times. A better solution is to remove the motor from the transport and after spraying in the DeoxIT to let it run for several minutes using an external power source between 4-9 Volts. This will help the motor brushed to scrap away the carbon in the dead spot. A more permanent solution is to disassemble the motor and use very fine grit sandpaper or steel wool to clean the stator while spinning the thing with and electric drill. Apply some DeoxIT and reassemble. There is one more possible solution. Replace the motor. Now these motors are no longer available from Nakamichi, but, two suitable replacements have been found that will require a few minutes of modification to the deck. The Mabuchi RF-370C-15370 motor from MCM Electronics for $32.65 (out of stock at last check) is a very close substitute. The Johnson RF-370C, P/N 174693 motor from Jameco Robot Store, for $2.49 has a slightly longer shaft, but, it will work fine. The mounting holes are 17mm apart on the motors and 16mm apart on the Nak transport. Take a small rat tail file and elongate the two holes on the transport to mount the new motor.
I decided that the best option for me was to “remove the motor from the transport and after spraying in the DeoxIT to let it run for several minutes using an external power source between 4-9 Volts. This will help the motor brushes to scrape away the carbon in the dead spot”. (Hopefully) The procedures explained below are to suit The Nakamichi BX300 deck but can possibly help with other Nak decks with the Sankyo transports. The BX300 is relatively easy as it does not require much disassembly and you don’t need to disturb the wiring loom or cut cable ties etc. There are a few things to watch for (as I discovered), but I will point them out along the way. Please read the text first before pulling anything to bits on each step.
RX-505 Dolby On-Off / Dolby B-C / Eq 70-120 switches no longer lock in place? Here’s the fix!
Found a direct gold-plated replacement for the ordinary RCA connectors.
This modification was tested on CR-1 and CR-2 but may also work on DR-2, DR-3, DR-8, Cassette Deck 1.5 and Cassette Deck 2 but with a different Pin Jack P.C.B. Ass'y. Other models in these series already have gold plated connectors.