Nakamichi BX-300 Discrete Head Cassette Deck

Introduction

Congratulations on choosing the Nakamichi BX-300, an excellent cassette deck incorporating Nakamichi's advanced technology, including the Discrete Three-Head system and Direct-Drive Asymmetrical, Diffused-Resonance Dual Capstan Transport. This deck is designed for outstanding performance and user-friendly features. Please read this manual thoroughly for optimal use and retain it for future reference.

Please record the Model Number and Serial Number in the space provided below. These numbers are located on the rear panel of the unit.

Model Number: Nakamichi BX-300

Serial Number: [Space for Serial Number]

Safety Instructions

CAUTION: RISK OF ELECTRIC SHOCK. DO NOT OPEN.

Refer servicing to qualified service personnel only.

The lightning flash with arrowhead symbol alerts users to the presence of uninsulated "dangerous voltage" within the enclosure, which may pose a risk of electric shock.

The exclamation point within an equilateral triangle alerts users to important operating and maintenance instructions found in the accompanying literature.

WARNING: TO PREVENT FIRE OR SHOCK HAZARD, DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE.

This equipment generates and uses radio frequency energy. If not installed and used properly according to manufacturer's instructions, it may cause interference to radio and television reception. It complies with FCC Rules Part 15 for Class B devices. However, interference may still occur in a particular installation. If interference is experienced, users are encouraged to try correcting it by:

• Reorienting the receiving antenna.
• Relocating the equipment with respect to the receiver.
• Moving the equipment away from the receiver.
• Plugging the equipment into a different outlet so that the equipment and receiver are on different branch circuits.

Consult a dealer or experienced technician for additional suggestions. The booklet "How to Identify and Resolve Radio-TV Interference Problems" from the U.S. Government Printing Office may also be helpful.

General Safety Precautions:

• Read all safety and operating instructions before use.
• Retain instructions for future reference.
• Heed all warnings on the appliance and in the instructions.
• Follow all operating and use instructions.
• Do not use near water (e.g., bathtub, sink, wet basement, swimming pool).
• Use only with a recommended cart or stand.
• Mounting to a wall or ceiling should only be done as recommended by the manufacturer.
• Ensure proper ventilation; do not block openings with beds, sofas, rugs, or place in built-in installations that impede airflow.
• Keep away from heat sources like radiators, heat registers, stoves, or other heat-producing appliances.
• Connect only to the specified power supply type.
• Do not defeat grounding or polarization means.
• Protect power-supply cords from being walked on or pinched, paying attention to plugs and exit points.
• Clean only as recommended by the manufacturer.
• Unplug the power cord during nonuse periods.
• Take care to prevent objects from falling into or liquids from spilling into the enclosure through openings.
• Servicing should only be performed by qualified personnel if the power cord is damaged, objects/liquids have entered the unit, the unit has been exposed to rain, it does not operate normally, or the enclosure is damaged.
• Do not attempt to service beyond what is described in the operating instructions.

On Cassette Tapes

Precautions

• C-120 cassettes have thin tape that can break or snag easily, stretch, and have low sensitivity. They are not recommended for high-fidelity recording.
• Do not pull tape from the cassette housing.
• Avoid turning cassette reels with fingers, which can cause tape slackening.
• Store tapes away from heat, high humidity, dust, and magnetic fields (e.g., from speakers, TV sets).

Cassette Tabs

To protect recordings from accidental erasure, remove the appropriate tab on the top edge of the cassette. The tab is located on the top left-hand corner of the side you are facing. Use a small screwdriver to push the tab down and break it off. Do not leave the broken tab in the recess. To record over a side where the tab has been removed, cover the tab opening with adhesive tape.

[Description: Two small diagrams illustrating the cassette tape's record protection tabs. One shows breaking off the tab for Side A, and the other shows breaking off the tab for Side B.]

Cassette Insertion and Removal

Insertion:

1. When the Eject button is pressed in stop mode, the cassette holder opens.
2. Insert the cassette with the exposed tape facing down and the label of the desired side facing you.
3. Gently push the cassette holder back into the panel.

Note: For tape and transport protection, only press the Eject button in stop mode.

Removal:

1. Press the Stop button.
2. Press the Eject button; the cassette holder opens.
3. Remove the cassette.

Connections

After consulting your amplifier or receiver's instructions, use the provided shielded RCA cables to make connections as shown. Ensure left and right channels are not mixed up. Turn off power to the deck and amplifier before connecting.

Headphones

Standard stereo headphones with an impedance of 8-150 ohms may be connected to the headphone jack.

Microphone Connections

The BX-300 has only line input facilities. For microphone use during recording, a separate microphone mixer with a line output must be connected to the deck's line input terminals. Nakamichi offers the optional MX-100 Microphone Mixer, which provides three inputs for left, right, and center blend (L+R) microphones. The MX-100 requires the separate PS-100 Power Supply.

Remote Control

The optional RM-200 remote control unit allows operation of the deck's tape transport functions from any convenient location.

[Diagram Description: A block diagram illustrating the connections for the Nakamichi BX-300. It shows connections from the BX-300's Line Terminals and Headphone Jack to a Preamplifier, Amplifier, or Receiver. It also shows connections to an AC Wall Outlet or Amplifier's AC Outlet for power. Optional components like the RM-200 Remote Control Unit, MX-100 Microphone Mixer, and PS-100 Power Supply are also depicted with their respective connection points.]

Controls and Features

[Diagram Description: A front panel view of the Nakamichi BX-300 cassette deck, with numbered controls and indicators. Key controls include Power Switch, Rewind Button, Fast-Forward Button, Eject Button, Counter Reset Button, Pause Button, Record Button, Play Button, Stop Button, Timer Switch, Pitch Control, Master Fader Buttons, Memory Switch, Auto Repeat Switch, Headphone Jack, and Cassette Holder. Indicators for Dolby NR and Peak Level Meters are also visible.]

(1) Tape Counter:

Starts at "0000" and indicates tape travel from "9999" to "-999". Press Counter Reset to return to "0000".

(2) Play Button:

Press ▶️ to start playback or recording (record-standby mode). Indicator lights up during operation.

(3) Stop Button:

Press ⏹️ to stop tape transport from any mode. Indicator lights up.

(4) Timer Switch:

Used for timer-activated recording or playback. Set to "Off" for normal operation.

(5) Pitch Control:

Adjusts tape speed during playback by approximately ±6% (one semitone).

(6) Pause Button:

Press ⏸️ to temporarily interrupt tape travel during recording or playback. Indicator lights up. Press Play to resume.

(7) Master Fader Buttons:

Allow smooth fade-in and fade-out during recording.

(8) Record Button:

Press ⏺️ to enter record-standby mode (recording indicator lights up). Pressing again during recording activates Rec Mute for the duration the button is held.

(9) Memory Switch:

When "On", the tape automatically stops at counter "0000" during rewind or fast-forward.

(10) Auto Repeat Switch:

When "On", auto repeat playback is performed.

(11) Peak Level Meters:

Indicate peak levels from -40 to +10 dB.

(12) Output Level Control:

Adjusts line output and headphone output levels.

(13) Input Level Controls:

Adjust recording levels for left and right channels.

(14) Bias Tune Control:

Fine-tunes the bias current.

(15) MPX Filter Switch:

Suppresses the 19-kHz multiplex carrier signal that can interfere with Dolby NR when recording FM stereo broadcasts. Set to "Off" otherwise.

(16) Tape Selector Switches:

Select the correct switch for the tape type during recording.

(17) Equalizer Switch:

Selects correct equalization for recording and playback based on tape type.

(18) Monitor Switch:

Set to "Tape" for playback monitoring or off-tape monitoring during recording. Set to "Source" to hear the input signal before recording, also used for bias fine adjustment.

(19) Dolby NR Switches:

Set the upper switch to "On" and the lower switch to "B" or "C" for Dolby B-type or C-type noise reduction, respectively. Corresponding indicators light up.

Dolby NR System

The Nakamichi BX-300 features Dolby B-type NR (approx. 10 dB noise reduction in high frequencies) and Dolby C-type NR (approx. 20 dB S/N ratio improvement from 2 kHz to 8 kHz). Use the "B" setting for tapes recorded with Dolby B-NR and "C" for tapes recorded with Dolby C-NR.

Precautions Before Operation

• The deck has a muting circuit active for about 4 seconds after power-on until circuits stabilize.
• If power is switched on while the Timer switch is set to "Rec" or "Play", recording or playback will start automatically. Ensure the Timer switch is "Off" when not using the timer function to prevent accidental erasure.
• If power is switched off by an external timer during playback or recording, the Eject button may become inoperable. Do not force it. Set the Timer switch to "Off", then switch the deck's power back on to remove the cassette.
• A special circuit takes up tape slack when a cassette is inserted. The left spindle may rotate slightly, and the tape counter may change slightly upon closing the cassette compartment or powering on. This is normal.
• Voltage Selector: The AC voltage is factory-set for the country of purchase. A voltage selector may be present to reset mains voltage for use in other countries. Note that safety regulations in some countries prohibit voltage selectors.

Operation

Playback

1. Set the Equalizer switch to the required position for the tape.
2. Set the Dolby NR switches to match the recording settings.
3. Set the Monitor switch to "Tape".
4. Press the Play button ▶️ to start playback.
5. Adjust the listening level using the Output Level control.

Note: Peak Level meters display the recorded level and are not affected by the Output Level control. The deck allows seamless mode changes (e.g., playback to rewind) without needing to press Stop.

Recording

1. Set Tape Selector switches and the Equalizer switch for the tape type.
2. Select desired Dolby NR settings. For FM recording, set the MPX Filter switch to "On".
3. Press the Record button ⏺️ to enter record-standby mode.
4. Set the Monitor switch to "Source" and adjust recording levels using the Rec Level controls while watching the Peak Level meters.
5. Press the Play button ▶️ to start recording.
6. To check recording quality, set the Monitor switch to "Tape". In "Source" mode, the input signal is heard. Press Pause ⏸️ for a short interruption; press Play ▶️ to resume.

Record Level Setting

Maintaining a high signal-to-noise ratio is crucial for good recordings. Setting the record level too low results in tape hiss; too high results in distortion. Use the following guidelines:

• Metal Tape: Adjust levels so indicators (approx. +8 dB) light up occasionally on signal peaks.
• Normal-Position, Chrome-Position Tapes: Adjust levels so indicators (approx. +5 dB) light up occasionally on signal peaks.

Note: These are general guidelines; actual requirements may vary with tape and source.

Timer Recording or Playback

1. Connect components as shown and power them on.
2. For timer recording, set the recording level. For timer playback, set the Output control level.
3. Set the deck's Timer switch to "Rec" for recording or "Play" for playback.
4. Set the external timer for the desired operation time.
5. At the set time, the timer will supply power, and recording or playback will start automatically.

Notes: Ensure the Timer switch is "Off" when not using timer functions. Timer recording is not possible if cassette record-protection tabs are removed.

Special Features

1. Rec Mute

Pressing the Record button ⏺️ again during recording mutes the signal for as long as the button is held. If the Monitor switch is set to "Source", line and headphone outputs are not muted, allowing continuous monitoring of the input signal.

2. Master Fader

Enables smooth fades during recording without manual adjustment of the input level control. Pressing the "Down" section gradually reduces the recording level to zero. Pressing "Up" restores it to the previous setting. Two fading speeds are available: fast (hold button) and slow (press and release quickly). The fading mode is indicated by indicator brightness. The fader operates only in record/record-standby modes.

3. Auto Repeat Playback

(1) Auto Repeat of One Complete Side: When the Auto Repeat switch is "On", the deck automatically rewinds to the tape start, plays, and repeats this cycle when the tape end is reached.

(2) Auto Repeat Between Tape Counter "0000" and Tape End: With both Auto Repeat and Memory switches set to "On", auto repeat occurs between counter "0000" and the tape end. This function is inoperative if the Timer switch is set to "Rec" or "Play".

[Diagram Description: A circular diagram illustrating the Auto Repeat function. It shows Tape Start, Recording/Playback/Fast-Forward, Tape End, and Rewind, indicating a continuous cycle.]

Matching the Cassette Deck to Various Cassette Tapes

This deck was calibrated at the factory with Nakamichi reference tapes. For optimal results, using Nakamichi tapes is recommended. When using other tapes, select from the following list:

Bias Tune Control

This control allows fine adjustment of the bias current. Reducing bias extends high-frequency response but increases distortion; increasing bias reduces distortion but limits high-frequency response. For tapes listed above, keep the Bias Tune control in the center click-stop position. For other tapes, adjust bias by comparing input and recorded signals. This can be done by recording FM interstation noise (approx. -30 to -20 dB) and switching the Monitor between "Source" and "Tape".

• If the recorded signal sounds brighter than the original, turn the Bias Tune control to the right (+).
• If the recorded signal sounds duller, turn it to the left (-).
• Repeat steps (1) and (2) while monitoring to minimize sound quality differences.

Maintenance

Cleaning

Regular cleaning of head surfaces and the transport section is crucial. Contamination from tape particles can cause drop-outs and degrade high-frequency response and wow-and-flutter. Clean approximately every 10 hours of use.

1. Remove the cassette holder cover and push the cassette holder back in.
2. Press the Play button ▶️ and clean the revolving pressure rollers by holding a cotton-tipped stick lightly against the roller on the side turning away from the capstan. Be careful not to catch the cotton tip between the roller and capstan.
3. Press the Pause button ⏸️ to release the pressure rollers from the capstans. Clean the capstans, heads, and tape guides with a cotton-tipped stick. Avoid excessive force and do not damage the tape, preloading guides, or tape-pad lifter. Ensure no cotton strands remain.

For severe contamination, use a small amount of commercially available cleaning fluid designed for audio equipment. Ensure all residue is completely dry before playing a tape.

[Diagram Description: An illustration showing the tape path components to be cleaned: Capstan, Tape-Pad Lifter, Preloading Guide, Erase Head, Playback Head, Record Head, Tape Guide, and Pressure Roller.]

Demagnetizing

After prolonged use, residual magnetism can build up in heads and capstans, causing noise and high-frequency erasure. Demagnetize these parts approximately every 50 hours of use with a Nakamichi DM-10 Demagnetizer or similar device. Refer to the demagnetizer's manual. Always switch the deck's power off before demagnetizing.

Lubrication

All important moving parts have long-life, oil-less bearings. Periodic lubrication is not necessary.

Cleaning the Faceplate

Clean the faceplate by wiping with a soft, dry cloth only. Do not use alcohol, solvents, ammonia, or abrasive cleaning agents.

Troubleshooting

Specifications

• Track Configuration: 4 tracks/2-channel stereo
• Heads: 3 (erase head × 1, record head × 1, playback head × 1)
• Motors:
  Tape Transport: FG servo brushless, slotless, coreless, DD motor (capstan drive) × 1, DC motor (reel drive) × 1
  Mechanism: DC motor (cam drive) × 1
• Power Source: 100, 120, 120/220-240, 220 or 240 V AC, 50/60 Hz (According to country of sale)
• Power Consumption: 27W max.
• Tape Speed: 1-7/8 ips. (4.8 cm/sec.) ±0.5%
• Wow-and-Flutter: Less than ±0.048% WTD Peak, Less than 0.027% WTD RMS
• Frequency Response: 20 Hz-20,000 Hz ±3 dB (recording level -20 dB, ZX, SX, EXII tape)
• Signal-to-Noise Ratio:
  Dolby C-Type NR on <70 μs, ZX tape>: Better than 70 dB (400 Hz, 3% THD, IHF A-WTD RMS)
  Dolby B-Type NR on <70 μs, ZX tape>: Better than 64 dB (400 Hz, 3% THD, IHF A-WTD RMS)
• Total Harmonic Distortion: Less than 0.9% (400 Hz, 0 dB, ZX tape), Less than 1.0% (400 Hz, 0 dB, SX, EXII tape)
• Erasure: Better than 60 dB (100 Hz, +10 dB)
• Separation: Better than 36 dB (1 kHz, 0 dB)
• Crosstalk: Better than 60 dB (1 kHz, 0 dB)
• Bias Frequency: 105 kHz
• Input (Line): 50 mV/30 kohms
• Output (Line): 1.0 V (400 Hz, 0 dB, output level control at max.) 2.2 kohms
• Headphones: 5 mW into 8 ohms (400 Hz, 0 dB, output level control at max.)
• Fast-Wind Time: Approx. 80 seconds (with C-60 cassette)
• Dimensions: 430 (W) × 100 (H) × 250 (D) mm / 16-15/16 (W) × 3-15/16 (H) × 9-7/8 (D) inches
• Approximate Weight: 5.6 kg, 12 lb 6 oz

Specifications and design are subject to change for further improvement without notice.

Noise Reduction System manufactured under license from Dolby Laboratories Licensing Corporation. The word "DOLBY" and the Double-D-Symbol are trademarks of Dolby Laboratories Licensing Corporation.

Optional Accessories

• ZX Metalloy Cassette Tape (C-60, C-90)
• SX II Super Ferricobalt Cassette Tape (C-60, C-90)
• SX Ferricobalt Cassette Tape (C-60, C-90)
• EX II Ferricrystal Cassette Tape (C-60, C-90)
• DM-10 Head Demagnetizer
• SF-10 Subsonic Filter
• SP-7 Stereo Headphones
• RM-200 Remote Control Unit

Manufacturer Information

Nakamichi Corporation
Tokyo Office
Shinjuku Daiichi Seimei Bldg.
2-7-1 Nishishinjuku, Shinjuku-ku, Tokyo
Phone: (03) 342-4461
Telex: 2324721 (NAKAM J)

Nakamichi U.S.A. Corporation
19701 South Vermont Avenue
Torrance, California 90502
Phone: (213) 538-8150

Nakamichi GmbH
Stephanienstrasse 6, 4000 Düsseldorf 1
Phone: (0211) 359036