marantz 2230b manual

The Marantz 2230B is a classic stereo receiver from the 1970s featuring 30 watts per channel, built-in AM/FM tuner, phono input for turntables, tape monitor, loudness control, and tone adjustments. Known for its distinctive blue-lit analog tuning dial and warm sound signature, this receiver delivers high-quality audio performance with robust construction. Below are key sections covering features, installation, operation, specifications, and maintenance.

Features at a Glance

Key components: Power amplifier, AM/FM stereo tuner, Phono preamp, Tone controls, Speaker selector.

Feature	Description
Power Output	30 watts per channel (8 ohms)
Tuner Section	AM/FM stereo with analog tuning dial
Inputs	Phono, Aux, Tape 1, Tape 2
Outputs	Speaker A/B, Headphone, Tape Rec
Tone Controls	Bass, Treble, Loudness contour
Filters	High and low filters
Power Switch	Main power on/off with indicator light
Volume Control	Analog potentiometer with smooth rotation
Balance Control	Left/right channel balance adjustment
Mode Selector	Stereo/Mono, FM muting

Installation

Unpack and inspect contents. Place on stable, well-ventilated surface.

1. Connect speakers: Use speaker wire to connect to Speaker A or B terminals.
2. Connect turntable: Use phono input for magnetic cartridges.
3. Connect audio sources: Use Aux input for CD players, tape decks, etc.
4. Connect antenna: FM dipole antenna for FM reception; AM loop for AM.
5. Plug into AC power outlet.

WARNING! Ensure proper ventilation; do not block heat sinks. Use correct speaker impedance (4-16 ohms).

First-Time Setup

Power on receiver; allow warm-up for optimal performance.

1. Select input source: Turn selector to Phono, Aux, or Tuner.
2. Tune FM stations: Use tuning dial and stereo indicator for best reception.
3. Adjust volume: Start at minimum, gradually increase to desired level.
4. Set tone controls: Begin at flat position (12 o'clock), adjust to preference.
5. Balance speakers: Use balance control to center sound between speakers.

CAUTION! Avoid turning volume to maximum to prevent speaker damage.

Specifications

• Power Output: 30 watts RMS per channel (8 ohms, 20Hz-20kHz)
• Total Harmonic Distortion: 0.3% at rated power
• Frequency Response: 10Hz-50kHz (+1, -3dB)
• Input Sensitivity: Phono: 2.5mV, Aux: 250mV
• Signal-to-Noise Ratio: Phono: 70dB, Aux: 85dB
• Tuner Section: FM sensitivity: 2.0μV, AM sensitivity: 50μV
• Dimensions: 17-1/2" W × 5-1/4" H × 14-1/2" D
• Weight: 22 lbs (10 kg)
• Power Requirements: 120V AC, 60Hz, 180W

Controls and Settings

Front panel controls: Power, Volume, Balance, Selector, Tone controls, Filters.

Main Controls: Power switch, Input selector (Phono, Aux, Tuner), Volume, Balance, Bass, Treble, Loudness, Mode (Stereo/Mono), Speaker selector (A/B/Off).

Tone Controls: Bass (±10dB at 50Hz), Treble (±10dB at 20kHz), Loudness (compensates for low-volume listening). Filters: High filter (cuts above 7kHz), Low filter (cuts below 70Hz). Tuner: Tuning dial, Signal strength meter, Stereo indicator, FM muting.

Connecting Components

Speaker connections: Binding posts for Speaker A and B. Inputs: Phono, Aux, Tape 1, Tape 2. Outputs: Headphone, Tape record.

1. Turn off power before making connections.
2. Connect turntable to Phono input (ground wire to ground terminal).
3. Connect CD player or other line-level sources to Aux input.
4. Connect tape deck to Tape 1 or Tape 2 inputs/outputs.
5. Connect FM antenna to 300Ω terminals; AM antenna to AM terminals.

Tip: Use high-quality cables and ensure secure connections for best performance.

Tuner Operation

AM/FM stereo tuner with analog tuning and signal strength meter.

1. Select Tuner on input selector.
2. Choose AM or FM band using mode selector.
3. Tune stations: Rotate tuning dial until signal meter peaks.
4. For FM stereo: Wait for stereo indicator to light for stereo reception.
5. Use FM muting to eliminate inter-station noise.
6. Fine tuning: Adjust for clearest reception and strongest meter reading.

WARNING! Proper antenna positioning is crucial for good reception.

Audio Adjustments

Tone controls and filters for customized sound.

1. Bass control: Adjust low frequencies (50Hz).
2. Treble control: Adjust high frequencies (20kHz).
3. Loudness: Engage for enhanced bass at low volume levels.
4. Balance: Adjust left/right channel balance.
5. Filters: Use high filter for reducing hiss; low filter for reducing rumble.
6. Mode: Select Mono for weak FM signals to reduce noise.

Care & Maintenance

Unplug before cleaning. Use soft, dry cloth for exterior; compressed air for controls.

CAUTION! Do not use liquids or solvents. Keep away from moisture and extreme temperatures. Have serviced by qualified technician if performance degrades.

Regulatory Information

FCC compliant for home use. Manufactured by Marantz Company, Inc. This product complies with applicable standards for audio equipment. For service or technical support, consult authorized Marantz service centers. Original documentation © Marantz.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No sound	Power/speaker connections	Check power cord; verify speaker connections; ensure speaker selector is on.
Distorted sound	Overload/incorrect settings	Reduce volume; check input level; verify tone controls at neutral.
Poor FM reception	Antenna/positioning	Reposition FM antenna; check connections; use external antenna for weak areas.
Hum from phono	Ground connection	Ensure turntable ground wire connected to ground terminal.
One channel silent	Balance/connections	Check balance control; verify cable connections; test with other source.
Lights not working	Bulbs/power	Replace dial lights; check power connection.

Service: Consult qualified audio technician for internal repairs.