Heineken's Garage

Introduction
At it's introduction, the NSX's audio system was considered a top-of-the-line equipment, centred around the Alpine made head unit. The internal size factor is double-DIN. Audio signals are provided to active speakers designed by Bose and specifically optimized for the NSX.

EU Specification Head Unit

JDM Specification Head Unit

Features
Depending on the target country the vehicle was produced for, the tuner has varying functionality. Cassette and CD changer functionality is identical across all build years and regions. Most feature-rich is the EU model, equipped with RDS (alphanumeric display), TPA and LW reception.
A mute pin is present for the optional in-car telephone.

Tuner	Cassette	CD Changer
Dual Antenna (JDM) Honda Alternative Select FM 87.5 ~ 108 MHz 0.05 MHz tuning (EU) FM 87.75 ~ 107.9 MHz 0.2 MHz tuning (USDM, 50 μs de-emphasis) FM 76 ~ 90 MHz 0.1 MHz tuning (JDM) RDS and TPA/TA (EU) AM 531 ~ 1602 kHz (EU) AM 535 ~ 1605 kHz (USDM) AM 522 ~ 1,629 kHz (JDM) LW 153 ~ 281 kHz (EU)	Normal, Chrome and Metal tape (auto detect) Fast forward and rewind Auto-reverse Track repeat, scan, skip forward and backwards Dolby B Clean notification	Six disks continuous play Disk selection Fast forward and rewind Track repeat, scan, random play, skip forward and backwards

FM reception with RDS enabled is subject to drop-outs every few seconds if the signals is not particularly strong. This behavior is related to the circuitry design employed at that time and not a defect.

Connections
The radio is equipped with a standard 1990s Honda connector for most of the signals going in and coming from the head unit. Additional connectors are for the trunk antenna, the rear window antenna (JDM specific) and a port for the optional 6-disk CD changer in the trunk.

Information Sticker on the Top of the Radio (EU)

Information Sticker on the Top of the Radio (JDM)

As the speakers contain their own amplifiers, the audio output from the radio is on line-out level and unable to drive regular speakers directly. It's a simple line output signal without a special frequency curve applied to it. Vehicle specific frequency shaping is realized by means of the speaker amplifiers.

Specialities
To match the centre console getting more slender towards the end, the radio's face plate is narrower at the bottom than at the top. The corresponding centre console cover and the arrangement of buttons reflects that, too. Using a standard double-DIN radio (with a custom centre console cover) instead of the stock head unit, is optically not an ideal solution and can create a feeling of being "slightly off".

Sound Quality
Cassette tape is rather noisy compared to good HiFi equipment of similar age. The Dolby noise reduction e.g. provides very little improvement due to the already relatively high noise floor of the tape deck. Metal tape cassettes provide only very little improvement over CrO² (Chrome) tape.
The radio reception and tuner audio quality is comparable to other high-quality car radios of the era.
CD playback is of much better quality, noticeably above radio and on par with CD-players from the beginning of the 90s. Using the CD changer input with an adapter for AUX-IN, Bluetooth or similar provides a more-or-less up-to-date audio quality.

Known Issues
Capacitor leakage is a problem for the head unit, the same way as for the Climate Control Unit (CCU), the speakers, the SRS (Airbag) ECU and the gauge cluster. Preventive capacitor replacement is highly suggested.
The single rubber belt employed in the cassette drive lengthens over time. This can cause issues with playback, fast-forward, reverse and the track skip/repeat function. Belt replacement is advised as soon as issues are observed.
Issues with cassette play can also be caused by grease hardening of the central plastic wheel that distributes the motor movement to either the left or right cassette tape take-up wheel. Cleaning with WD40 an re-application of silicon grease is sufficient to fix this problem.