Marantz 3250 Manual

The Marantz 3250 is a high-performance stereo preamplifier featuring multiple inputs, tone controls, tape monitoring, and advanced audio processing capabilities. Designed for audiophiles, it delivers exceptional sound quality with precise control over audio parameters. Below are key sections for safety, features, installation, setup, operation, and troubleshooting.

Features at a Glance

Key components: High-quality preamplifier circuitry, multiple input/output options, tone controls, tape monitoring, and advanced audio processing.

Feature	Description
Input Selector	Multiple source selection (Phono, Tuner, Aux, Tape)
Tone Controls	Bass, Midrange, and Treble adjustment
Loudness Control	Compensates for low-volume listening
Tape Monitoring	Dual tape monitor circuits
Balance Control	Left/Right channel balance adjustment
Filter Controls	High and low frequency filters
Power Switch	Main power on/off control
Volume Control	Precision stepped attenuator
Headphone Jack	For private listening
Output Level	Adjustable output for power amplifier

Installation

Unpack and inspect contents. Place on stable, vibration-free surface.

1. Connect audio sources: Use appropriate input jacks for turntable, tuner, CD player, etc.
2. Connect to power amplifier: Use main output jacks to amplifier inputs.
3. Connect tape decks: Use tape monitor inputs/outputs for recording/playback.
4. Plug into AC power outlet.

WARNING! Ensure proper ventilation; do not block heat sinks. Use quality interconnects for best performance.

First-Time Setup

Power on preamplifier; verify all connections are secure.

1. Select input source: Turn INPUT SELECTOR to desired source (Phono, Tuner, Aux).
2. Adjust volume: Start with volume at minimum, gradually increase to desired level.
3. Set tone controls: Begin with flat response (center position).
4. Balance channels: Use BALANCE control to center soundstage.
5. Engage filters: Use HIGH and LOW filters as needed for noise reduction.

CAUTION! Always power off when making connections. Avoid shorting outputs.

Specifications

• Type: Stereo Preamplifier
• Inputs: Phono (MM), Tuner, Aux, Tape 1, Tape 2
• Outputs: Main Out, Tape Out 1, Tape Out 2
• Frequency Response: 20Hz-20kHz ±0.5dB
• Total Harmonic Distortion: <0.05%
• Signal-to-Noise Ratio: >90dB
• Tone Control Range: ±10dB at 100Hz (Bass), ±10dB at 10kHz (Treble)
• Input Sensitivity: Phono: 2.5mV, High Level: 150mV
• Power Requirements: 120V AC, 60Hz, 15W
• Dimensions: Standard component width (17")

Controls and Settings

Front Panel: POWER, INPUT SELECTOR, VOLUME, BALANCE, TONE CONTROLS, FILTERS, LOUDNESS, TAPE MONITOR.

Input Selection: Phono, Tuner, Aux 1, Aux 2, Tape 1, Tape 2. Tone Controls: Bass (±10dB), Midrange (±8dB), Treble (±10dB). Filters: High Cut (7kHz), Low Cut (70Hz). Loudness: Compensates for Fletcher-Munson curves.

Tape Monitoring: Allows monitoring of tape decks during recording. Balance: Adjusts left/right channel levels. Muting: -20dB muting function.

Connecting Devices

Multiple input/output options for complete system integration.

1. Turntable: Connect to PHONO inputs (use ground wire).
2. Tuner: Connect to TUNER inputs.
3. CD Player: Connect to AUX inputs.
4. Tape Decks: Connect to TAPE 1/TAPE 2 inputs and outputs.
5. Power Amplifier: Connect MAIN OUTPUT to amplifier inputs.
6. Headphones: Connect to front panel headphone jack.

Tip: Use high-quality shielded cables. Keep signal cables away from power cords.

Audio Processing

Advanced audio control and processing capabilities.

1. Tone Adjustment: Use BASS, MIDRANGE, TREBLE controls to tailor sound.
2. Loudness Compensation: Engage LOUDNESS for improved low-volume listening.
3. Filter Application: Use HIGH/LOW filters to reduce noise and interference.
4. Tape Monitoring: Monitor tape recording quality in real-time.
5. Source Comparison: Easily switch between sources for A/B testing.
6. Balance Control: Perfect stereo image placement.
7. Muting: Temporary volume reduction without resetting main volume.

WARNING! Avoid extreme tone control settings which may cause distortion.

Maintenance

Regular maintenance ensures optimal performance and longevity.

Clean controls periodically with contact cleaner. Keep unit free of dust. Check connections annually for corrosion. Ensure adequate ventilation.

CAUTION! Unplug before cleaning. Do not use abrasive cleaners. Service by qualified technicians only.

Regulatory Information

FCC Part 15: Class B digital device; complies with interference limits for residential use. Copyright © Marantz; all rights reserved. Manufactured to meet industry standards for audio equipment. For support and service, contact authorized Marantz service centers.

Troubleshooting

Symptom	Possible Cause	Corrective Action
No sound from one channel	Balance control/Cable	Check balance setting; verify cable connections; swap channels to isolate issue.
Hum or noise	Grounding/Cables	Ensure proper grounding; use shielded cables; check for ground loops.
Distorted sound	Input overload	Reduce source output level; check phono cartridge alignment.
Controls noisy	Dirty contacts	Clean controls with contact cleaner; exercise controls regularly.
Intermittent operation	Loose connections	Check all cable connections; inspect internal wiring if qualified.

Service: Contact authorized Marantz service center for internal repairs.

Support: Refer to manufacturer's website for technical documentation and updates.