Marantz 4400 Flagship Quadraphonic Receiver – Custom Black – WC-43 Wood Case – Restored – 1-Year Warranty

Professionally Restored by HQaudios – Fully Tested – Backed by Our 1-Year Warranty.

Up for sale is the Marantz 4400, the flagship of Marantz’s quadraphonic receiver line from the mid-1970s (circa 1974–1978) and one of the most sought-after Marantz receivers of the era.

The defining feature of the 4400 is its built-in CRT oscilloscope, used for precise multipath tuning and real-time audio waveform display. Its four independent amplifier channels deliver 50 watts each in quadraphonic mode and can be bridged to 125 watts per channel in stereo. The 4400 also features the iconic Gyro-Touch tuning wheel, built-in Dolby noise reduction, Vari-Matrix synthesis, and a socket for optional matrix/CD-4 decoders.

This unit has been professionally restored, serviced, and tested by HQaudios while preserving the original engineering and warm analog character of the Marantz 4400. This particular unit features a custom black front-panel finish and comes with the Marantz WC-43 walnut wood case, as pictured, included at no extra cost.

Please note: the AM/FM tuner section of this unit is not functional – the tuning capacitor is damaged and no replacement part is available. The amplifier, phono stage, tape inputs, quadraphonic/Vari-Matrix circuitry and the oscilloscope have been serviced and tested, so this receiver is offered as an amplifier / phono / oscilloscope unit with a non-working tuner.

Key Highlights

• Authentic Marantz 4400 Flagship Quadraphonic Receiver
• Custom Black Front-Panel Finish
• Built-in CRT Oscilloscope for multipath tuning and audio waveform display
• 125 Watts x 2 (Stereo, bridged) or 50 Watts x 4 (Quadraphonic) into 8 Ohms
• Dolby Noise Reduction and Vari-Matrix Circuit
• Please note: AM/FM tuner not functional (damaged tuning capacitor, no replacement available) – see description
• Marantz WC-43 Walnut Wood Case Included – as pictured
• Professionally Restored and Serviced by HQaudios
• Real-world operational and listening test performed
• Carefully packed for safe delivery (approx. 53 lbs)
• Backed by Our 1-Year HQaudios Warranty

Sound Character

The Marantz 4400 delivers the quintessential “Three-Dimensional Marantz Sound” backed by the generous headroom of one of Marantz’s most powerful receivers of the 1970s. It provides a warm, lush, and tube-like sonic signature that makes long listening sessions a pleasure.

When run in traditional 2-channel stereo mode, the bridged 125 watts per channel provides a deeply anchored, authoritative low-end that easily grips and controls the most demanding, power-hungry vintage woofers. In quadraphonic mode, the receiver creates an incredibly immersive, holographic soundstage, surrounding the listener with lifelike instrumentation and air.

Equipped with an excellent built-in phono stage, this receiver brings analog vinyl records to life with real warmth and detail. (The AM/FM tuner section is not functional on this unit – see the note above and the Specifications section.)

Cosmetic Condition

This unit is in Very Good restored vintage cosmetic condition, with visible but moderate age-related wear consistent with a 1970s component.

Please review all photos carefully, as they are an important part of the description.

• Custom Black Front Panel: This unit features a custom black front-panel finish. The lettering and controls remain clearly readable.
• Dial Glass / Front Glass: The front glass shows light surface scratches and scuffs visible under close inspection and certain lighting angles. These marks are cosmetic and should be considered part of the unit’s vintage condition.
• Oscilloscope CRT: The screen is clear, producing a bright and responsive trace.
• Knobs / Controls / Sliders: The knobs, push-buttons, and balance sliders are intact and operate after service.
• Top Heat-Sink / Vent Area: A few of the metal cooling fins / vent slots show minor bending. This area is largely covered from normal view when the included WC-43 wood case is installed.
• Wood Case: The included Marantz WC-43 walnut wood case presents well overall with normal age-related wear and covers the top chassis / cooling area during normal use.
• Rear Panel / Connections: Speaker terminals, RCA inputs, AM ferrite antenna, and rear-panel hardware are present and securely mounted.

HQaudios Restoration & Testing Process

Specifications

What Is Included

Marantz 4400 Flagship Quadraphonic Receiver

Marantz WC-43 Walnut Wood Case – included at no extra cost, as pictured

Only the items clearly shown in the photos or specifically listed in the description are included.

Video Test & Sound Demo

If you would like to see or hear the Marantz 4400 in operation (including the oscilloscope display) before purchase, please message us directly via platform messaging.

For additional operational photos or video demos, we are happy to provide them upon request via platform messages.

Suggested Pairing

The Marantz 4400 pairs exceptionally well with massive vintage acoustic suspension or high-efficiency speakers that can handle its bridged 125-watt power output.

For the best performance, ensure that all connected equipment is electrically and mechanically compatible with the receiver and properly configured before use.

Basic Use Guide

To help maintain the long-term performance of this massive flagship receiver, we recommend the following:

• Verify operating mode: The rear panel switch must be set correctly to either 125W x2 (Stereo) or 50W x4 (Quadraphonic) before powering on. Do not switch this mode while the unit is operating.
• Oscilloscope CRT Care: To prevent phosphor screen burn-in on the vintage CRT, turn down the intensity knob when not actively viewing the oscilloscope, and never leave a bright, stationary dot on the screen for extended periods.
• Ventilation is critical: The 4400 generates significant heat due to its massive power supply and four independent amplifiers. Ensure adequate breathing room above the top chassis vents. Never stack other equipment on top of this receiver.
• U.S. power: This unit is intended for standard 120V AC / 60Hz operation in the United States.
• Please message us via platform messaging if assistance with setup or speaker matching is needed.

Trade-In Program

Do you have vintage audio equipment you’d like to trade in?

HQaudios welcomes trade-ins on receivers, amplifiers, speakers, cassette decks, reel-to-reel decks, turntables, and other classic audio equipment.

Simply send us photos and basic information about your equipment via platform messaging. Our team will review the item and discuss available trade-in options.

Build Your Vintage System / Combo Discount

Looking to build a complete vintage audio system?

HQaudios can help match the Marantz 4400 with compatible vintage audio components (or a custom wood cabinet).

Save $100 when purchasing this receiver together with a qualifying restored vintage audio component from HQaudios.

Please message us via platform messaging before checkout to apply the bundle offer.

Shipping & Packaging

Vintage monster receivers are incredibly heavy and delicate. This 53-lb unit will be carefully packed by HQaudios for safe delivery.

• Protective wrapping applied securely around the chassis and faceplate.
• Heavy-duty packing materials used to absorb impact.
• Extra CRT screen, Gyro-Touch wheel, knob, and rear connection protection.
• Tracking information provided immediately upon shipment.
• Signature may be required upon delivery.

1-Year HQaudios Warranty

This unit is backed by our 1-Year HQaudios Warranty, covering normal-use functionality related to the service work performed by HQaudios.

If an issue occurs, please message us via platform messaging first. Our team will help evaluate the issue and work toward an appropriate solution.

The warranty does not cover misuse, improper setup, unauthorized repair, physical damage, cosmetic wear, amplifier clipping, CRT burn-in from improper use, excessive power, incorrect wiring, incompatible equipment, or operation outside the manufacturer’s intended specifications. The non-functional AM/FM tuner section is sold as-is and is excluded from warranty coverage.

Customer Service

After delivery, customers may message us via platform messaging for assistance with setup, connections, equipment matching, and model-specific settings.

Our team is happy to help customers use their vintage audio system correctly and confidently.

Important Note for Vintage Audio Buyers

This is vintage audio equipment, so minor signs of age may be present and are normal for equipment that has been in use for many years.

Vintage audio equipment must be connected and operated correctly. Always verify voltage configuration, speaker impedance, and other model-specific operating requirements before powering on the system.

HQaudios – Vintage Audio Restored with Care.
Backed by Our 1-Year Warranty.