Marantz 2440 Quadradial 4 Power Amplifier

The Marantz 2440 is a rare and highly respected Quadradial 4-channel power amplifier from Marantz’s golden era, designed specifically for quadraphonic and advanced multi-channel audio systems of the 1970s. Unlike conventional stereo amplifiers, the 2440 delivers true four-channel amplification with remarkable clarity, balance, and control—making it a standout piece for collectors and quadraphonic enthusiasts.

Featuring the iconic silver brushed aluminum faceplate, four illuminated blue VU meters, and Marantz’s unmistakable industrial design, the 2440 is both a technical statement and a visual centerpiece. Its robust internal construction and conservative power ratings ensure stable operation and musical authority across all channels.

This unit has been professionally serviced by HQaudios, ensuring reliable performance, accurate channel balance, and long-term durability while preserving its original vintage character and collectible value.

Condition: Excellent – Serviced, tested, and cleaned

Model: Marantz 2440

Type: 4-Channel Quadradial Power Amplifier

Protection Plan: 1-Year Warranty Included

Free Support: Must be used before requesting return

Packaging: Securely packed, insured, and tracked

ACCESSORIES: Wood case

SKU: 1THLC0230

Customer Service:

Once your item arrives, if you have questions about how your item functions or proper settings, please CONTACT US.

TRADE-IN PROGRAM

“If you have any vintage audios (receivers, speakers, cassette, reel to reel…) & want to upgrade with the serviced one, don’t hesitate to contact us for the best deal. You only need to pay for the difference between yours & mine….”

Note:

The actual color of the product may sometimes differ slightly from the photos due to lighting conditions, temperature, and the device used. Some angles in the photos may not fully reflect the product’s condition. Please read the description carefully and feel free to message us if you have any questions.

SPECS

Power output: 20W/ch into 8Ω (stereo)

Frequency response: 5Hz to 45kHz

Total harmonic distortion: 0.3%

Damping factor: 45

Input sensitivity: 150mV (line)

Signal to noise ratio: 80dB (line)

Channel separation: 30dB (line)

Output: 1V (Pre out)

Dimensions: 17-1/3 x 5-1/3 x 14-3/8 inches

Weight: 24.2lbs

KEY FEATURES

True 4-Channel Amplification: Designed for quadraphonic and multi-speaker systems

Power Output: Stable and balanced output across all four channels

VU Meters: Four independent illuminated meters for real-time monitoring (Front L/R – Rear L/R)

Marantz Sound Signature: Smooth, warm, and musical presentation with excellent midrange clarity

Controls: Individual front/rear balance, master volume, and mode selection

Headphone Output: Rear headphone jack for quad monitoring

Build Quality: Heavy-duty chassis with oversized power supply for long-term reliability

Design: Classic Marantz silver faceplate with deep blue meter illumination

REFURBISHED

This Marantz 2440 has undergone a comprehensive professional servicing process by HQaudios to restore performance, stability, and operational accuracy while maintaining its original appearance.

1. Fully Serviced

• Silver brushed aluminum faceplate carefully cleaned and detailed; although thorough cleaning reveals some scratches and faded lettering due to previous use.
• All knobs, switches, and sliders cleaned with DeoxIT and lubricated for smooth, noise-free operation
• Mode selector, dimension control, and remote/local controls tested for proper function
• Input/output terminals cleaned and re-tensioned
• Rear headphone output tested for clean, balanced quad playback
• Internal chassis cleaned and dusted
• Rear panel cleaned with markings preserved

2. Electronic Inspection & Restoration

• Power supply inspected and stabilized for consistent voltage delivery across all channels
• Aging or out-of-spec components replaced where necessary
• DC offset and channel balance checked and adjusted
• Heat-stressed solder joints reflowed to improve long-term reliability

3. Meter & Display System

• All four VU meters tested for accurate response and smooth needle movement
• Meter illumination verified for even brightness and correct blue tone
• Signal tracking confirmed for front and rear channels

4. Final Testing & Quality Control

• Extended multi-channel operation testing to confirm thermal stability
• All inputs and outputs tested for clean, noise-free signal
• Channel balance and output consistency verified across all four channels
• Final listening tests performed to ensure smooth, distortion-free quadraphonic playback

Result:
Despite being thoroughly refurbished, there are still a few scratches on the aluminum surface and some faded lettering; however, the product still delivers excellent sound quality.

SUGGESTED PAIRINGS

• Quadraphonic Preamps: Marantz 3300 / 3600, Marantz 4400 (Pre-Out)
• Speakers: Four matched vintage speakers such as JBL, Advent, KLH, or AR
• Sources: Quadraphonic reel-to-reel decks, turntables with quad cartridges, vintage quad decoders

🎁 Unlock an instant $100 voucher with every combo purchase.

PACKAGING & SHIPPING

Secure Packaging:

• High-density foam inserts with 5-layer corrugated cartons
• Additional internal padding and wrap for transit protection

• Double-wall outer box with corner guards and straps

Shipping Details:

• Dispatch Time: Ships within 3 business days

• Carrier: UPS Ground (tracked & insured)

• Signature Required: Yes (as buyer’s request)

• Transit Time: Typically 3–7 business days (USA)

International Shipping:

 We offer global delivery through the eBay International Shipping Program. eBay handles customs, duties, and tracking.

📦 Note: Packaging may vary slightly depending on unit size or availability, but safety and protection are always our top priority.