Marantz 510M Manual

The Marantz 510M is a high-performance stereo power amplifier featuring 125 watts per channel RMS into 8 ohms, 20Hz to 20kHz with no more than 0.1% total harmonic distortion. This professional-grade amplifier includes dual VU meters, balanced XLR inputs, speaker protection circuitry, thermal protection, and professional-grade binding posts. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

Features at a Glance

Key components: High-power amplifier circuitry, Dual VU meters, Balanced XLR inputs, Professional binding posts, Speaker protection relay.

Feature	Description
Power Output	125 watts per channel RMS into 8 ohms
THD	Less than 0.1% at rated output
Frequency Response	20Hz to 20kHz ±0.5dB
Input Sensitivity	1V for 125W output
Input Impedance	47k ohms unbalanced, 20k ohms balanced
Damping Factor	Greater than 100 at 8 ohms
Signal-to-Noise Ratio	110dB (A-weighted)
VU Meters	Dual meters with peak hold function
Protection Circuits	DC offset, thermal, short circuit protection
Power Requirements	120V AC, 60Hz, 500W maximum

Installation

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

1. Position amplifier: Ensure adequate ventilation (minimum 6 inches clearance on all sides).
2. Connect speakers: Use high-quality speaker wire to binding posts (observe polarity).
3. Connect source components: Use balanced XLR or unbalanced RCA inputs.
4. Connect AC power: Use included power cord to grounded outlet.

WARNING! Amplifier generates significant heat; ensure proper ventilation. Use two people for handling due to weight.

First-Time Setup

Power on amplifier; observe startup sequence.

1. Connect speakers: Ensure proper impedance matching (4-16 ohms).
2. Connect preamplifier: Use balanced XLR for best performance.
3. Power sequence: Turn on source components first, then amplifier.
4. Initial testing: Start with volume at minimum, gradually increase.
5. Monitor VU meters: Ensure proper signal levels.

CAUTION! Always observe proper power sequencing to prevent damage to speakers.

Specifications

• Power Output: 125W RMS per channel into 8 ohms (20Hz-20kHz)
• Total Harmonic Distortion: <0.1% at rated output
• Frequency Response: 20Hz-20kHz ±0.5dB
• Input Sensitivity: 1V for 125W output
• Input Impedance: 47k ohms (unbalanced), 20k ohms (balanced)
• Damping Factor: >100 at 8 ohms
• S/N Ratio: 110dB (A-weighted)
• Power Consumption: 500W maximum
• Dimensions: 17" W × 5.5" H × 14" D
• Weight: 35 lbs

Controls and Settings

Front Panel: POWER switch, VU meters, Meter sensitivity switch.

Rear Panel: Balanced XLR inputs, Unbalanced RCA inputs, Speaker binding posts, AC power connector, Ground terminal.

Meter Operation: VU meters display output power; sensitivity switch adjusts meter range. Input Selection: Use balanced XLR for professional applications, RCA for consumer gear. Speaker Connections: Use high-quality cables; observe polarity for proper phase.

Connecting Devices

Sources: Balanced XLR or unbalanced RCA inputs. Speakers: Professional binding posts.

1. Turn off all components before making connections.
2. Connect preamplifier: Use XLR cables for balanced operation.
3. Connect speakers: Tighten binding posts securely.
4. Connect AC power: Use grounded outlet only.
5. Check all connections before powering on.

Tip: Use high-quality, shielded cables for best performance and noise rejection.

Operation Guidelines

Professional power amplifier operation procedures.

1. Power sequencing: Sources first, then amplifier.
2. Volume control: Use preamplifier for volume adjustment.
3. Monitor VU meters: Keep peaks below 0dB for clean operation.
4. Thermal management: Ensure adequate ventilation during extended use.
5. Shutdown sequence: Amplifier first, then sources.
6. Meter interpretation: -20dB = 1.25W, 0dB = 125W into 8 ohms.
7. Input level matching: Adjust preamplifier output for optimal performance.

WARNING! Do not operate without proper load. Avoid shorting speaker outputs.

Protection Features

DC Offset Protection: Automatically disconnects speakers if DC detected. Thermal Protection: Shuts down amplifier if overheating occurs. Short Circuit Protection: Protects against output shorts. Soft Start: Prevents power surge at turn-on.

Care & Maintenance

Unplug before cleaning. Use soft, dry cloth for exterior. Keep ventilation openings clear of dust.

CAUTION! Do not use liquid cleaners. Internal service should be performed by qualified technicians only.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits. UL Listed: Meets safety standards. Copyright © 1978 Marantz Company, Inc. All rights reserved. For service, contact authorized Marantz service centers.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No sound output	Protection triggered	Check speaker connections; ensure no shorts; allow cool-down if thermal protection active.
Distorted sound	Overload or clipping	Reduce input level; check source material; verify proper impedance matching.
Amplifier shuts down	Thermal protection	Ensure adequate ventilation; check ambient temperature; reduce output levels.
VU meters not moving	No input signal	Check source connections; verify preamplifier operation; test with known good source.
Hum or noise	Ground loops/cables	Check cable shielding; verify proper grounding; use balanced connections.

Reset: Power cycle amplifier to reset protection circuits.

Service: Contact authorized Marantz service center for internal repairs.