marantz model 27 manual

The Marantz Model 27 is a classic stereo receiver featuring 30 watts per channel RMS power output, AM/FM stereo tuner, magnetic phono input, tape monitor circuits, loudness contour, and comprehensive tone controls. This high-fidelity component delivers exceptional audio performance with Marantz's renowned build quality and distinctive blue-lit tuning dial. Below are key sections covering features, installation, operation, specifications, and maintenance.

1. Features at a Glance 2. Installation 3. First-Time Setup 4. Specifications 5. Controls and Settings 6. Connecting Components 7. Tuner Operation 8. Audio Adjustments 9. Care & Maintenance 10. Regulatory Information 11. Troubleshooting

Features at a Glance

Key components: Stereo amplifier section, AM/FM stereo tuner, Phono input, Tape monitor circuits, Front panel controls, Wooden cabinet.

Feature	Description
Power Output	30 watts per channel RMS (8 ohms)
Tuner Section	AM/FM stereo with FET front end
Phono Input	Magnetic cartridge input with RIAA equalization
Tape Monitor	Dual tape monitor circuits for recording
Loudness Control	Compensates for low-volume listening
Tone Controls	Separate bass and treble controls
Input Selector	Phono, Aux, Tape 1, Tape 2
Speaker Selector	A, B, or A+B speaker outputs
Headphone Jack	Front panel 1/4" stereo headphone output
Power Switch	Main power on/off with indicator light

Installation

Unpack and inspect contents. Place on stable, level surface.

Connect speakers: Use speaker wire to connect to A and/or B speaker terminals.
Connect turntable: Use phono input for magnetic cartridge turntables.
Connect auxiliary sources: Use AUX input for CD players, tape decks, etc.
Connect antenna: FM 300-ohm twin lead or 75-ohm coaxial; AM loop antenna.
Plug into AC power outlet.

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

First-Time Setup

Power on receiver; allow 30 seconds for warm-up.

Select input: Turn INPUT SELECTOR to desired source (Phono, Aux, Tape).
Adjust volume: Start with volume at minimum, gradually increase.
Tune FM stations: Use TUNING knob and STEREO indicator for stereo broadcasts.
Set tone controls: Begin with bass and treble at 12 o'clock position.
Engage loudness: Use LOUDNESS switch for low-volume listening enhancement.

CAUTION! Always turn volume to minimum before powering on or changing inputs.

Specifications

Power Output: 30 watts per channel RMS at 8 ohms.
Frequency Response: 20Hz to 20kHz ±1dB.
Total Harmonic Distortion: Less than 0.3% at rated power.
Input Sensitivity: Phono: 2.5mV; Aux: 150mV.
Signal-to-Noise Ratio: Phono: 65dB; Aux: 85dB.
Tuner Section: FM sensitivity: 2.0μV; AM: 50μV.
Tone Controls: Bass: ±10dB at 100Hz; Treble: ±10dB at 10kHz.
Power Requirements: 120V AC, 60Hz, 150 watts.
Dimensions: 17-1/2" W × 5-1/4" H × 14-1/2" D.

Controls and Settings

Front Panel: POWER, INPUT SELECTOR, VOLUME, BALANCE, BASS, TREBLE, LOUDNESS, TUNING, FUNCTION SELECTOR.

Rear Panel: Speaker terminals, Phono/Aux/Tape inputs, Antenna connections, AC power cord.

Input Selection: Phono (magnetic), Aux, Tape 1, Tape 2. Tone Controls: Separate bass and treble with center detent. Loudness: Compensates for Fletcher-Munson curves. Balance: Adjusts left/right channel balance. Speaker Selection: A, B, or A+B outputs.

Connecting Components

Speaker Connections: A and B speaker terminals accept bare wire or spade lugs. Source Connections: Phono input for turntable; Aux for CD player; Tape for recorders.

Turn off power before making connections.
Connect speakers observing proper polarity (+/-).
Use high-quality shielded cables for phono and auxiliary inputs.
Connect FM antenna to 300-ohm terminals or 75-ohm connector.
Ensure all connections are secure and tight.

Tip: Keep signal cables away from power cords to minimize hum.

Tuner Operation

AM/FM stereo tuner with tuning meter and stereo indicator.

Select tuner: Set FUNCTION to FM or AM.
Tune station: Rotate TUNING knob for desired station.
Fine tuning: Use tuning meter for precise station alignment.
Stereo reception: STEREO indicator lights when receiving stereo FM broadcast.
Muting: Automatic muting reduces interstation noise on FM.

WARNING! Do not force tuning knob; turn gently for accurate tuning.

Audio Adjustments

Tone Controls: Bass ±10dB at 100Hz; Treble ±10dB at 10kHz. Loudness: Engages bass boost at low volumes. Balance: Adjusts relative volume between left and right channels.

Care & Maintenance

Unplug before cleaning. Use soft, dry cloth for exterior; vacuum ventilation slots periodically.

CAUTION! Do not use chemical cleaners on wood cabinet. Avoid liquid contact with controls.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits for residential use. Copyright © 1970s Marantz Company; trademarks of Marantz America. For technical support or service, contact authorized Marantz service centers.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No sound from speakers	Speaker connections/input selection	Check speaker wires; verify input selector position; ensure volume up.
Hum in phono input	Ground connection/turntable	Connect turntable ground wire; check cartridge connections.
Poor FM reception	Antenna alignment/connection	Reposition FM antenna; check antenna connections; use outdoor antenna.
One channel silent	Balance control/cable	Adjust balance control; check interconnecting cables; swap L/R inputs.
Distortion at high volume	Overload/clipping	Reduce volume; check source signal level; verify speaker impedance.

Reset: Power cycle unit if abnormal operation occurs.

Service: Contact authorized Marantz service center for internal repairs.