Nakamichi MB-4s

The Nakamichi MB-4s is a curious entry in the company's cassette deck lineup — curious because the name collides with Nakamichi's own MusicBank CD changer line of the same era. But the verified record is clear: the MB-4s was a stereo cassette deck, not a CD player. The magazine advertising of the period, however, tells a different story — Audio (October 1993, p.3) ran a full-page ad featuring Ray Manzarek of the Doors touting "the new MB-4s" as a 7-disc MusicBank CD player. That same ad copy appeared in HiFI-Stereo across several months in 1993–1994. Whether this was a model-number collision, a regional naming difference, or a marketing mix-up is not documented. What the Japanese specification record shows is unambiguous: a three-head, auto-reverse cassette deck.

What's actually documented about the deck itself comes from a single Japanese source (audio-heritage.jp), and no spec is corroborated by a second independent source. The MB-4s used a quartz-locked direct-drive motor and a three-head configuration with crystal sendust heads for both record and playback, plus a separate erase head. It offered a 4-track, 2-channel stereo recording system, Dolby B and C noise reduction, an AMS music search system, auto-reverse, and a tape selector for Normal, CrO₂, and Metal formulations. Signal-to-noise was rated at 60 dB (Dolby off, weighted), wow and flutter at 0.05% WRMS, and frequency response at 20 Hz–20 kHz ±3 dB on Normal tape. It measured 430 × 130 × 245 mm and weighed 5.2 kg.

One spec conflict exists: a hifi-wiki.com listing gives frequency response as 50 Hz–15 kHz ±3 dB — likely a transcription error, as that figure appears to be a wow-and-flutter-style bandwidth statement rather than a genuine frequency response rating. The audio-heritage.jp figure is used above.

No production years, original price, or reception data have surfaced. If you own an MB-4s deck — or the MusicBank CD player that shared its name — the archive would welcome photographs and any documentation.

Type: Stereo cassette deck
Recording system: 4-track, 2-channel stereo
Heads: Crystal sendust (record/playback), erase — three-head configuration
Motor: Quartz-locked direct drive
Wow and flutter: 0.05% WRMS
Frequency response: 20 Hz – 20 kHz ±3 dB (Normal tape)
S/N ratio: 60 dB (Dolby off, weighted)
Noise reduction: Dolby B and C
Features: Auto-reverse, AMS music search, tape selector (Normal/CrO₂/Metal)
Dimensions: 430 × 130 × 245 mm
Weight: 5.2 kg