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OSCA Vintage Collection

*RARE* Phoenix Gold QX300.4 Vintage Car Audio Amplifier (New-Old-Stock)
*RARE* Phoenix Gold QX300.4 Vintage Car Audio Amplifier (New-Old-Stock)
*RARE* Phoenix Gold QX300.4 Vintage Car Audio Amplifier (New-Old-Stock)
*RARE* Phoenix Gold QX300.4 Vintage Car Audio Amplifier (New-Old-Stock)
*RARE* Phoenix Gold QX300.4 Vintage Car Audio Amplifier (New-Old-Stock)
*RARE* Phoenix Gold QX300.4 Vintage Car Audio Amplifier (New-Old-Stock)

Vendor:Phoenix Gold

*RARE* Phoenix Gold QX300.4 Vintage Car Audio Amplifier (New-Old-Stock)

Sale price$299.00Regular price $425.00

Early 2000's Car Audio Phoenix Gold QX300.4 Black 4-Channel MOSFET Amplifier | New Old Stock (NOS)

The Phoenix Gold QX300.4 Black is a four-channel power amplifier from the early-2000s generation of Phoenix Gold's QX series. Featuring a distinctive black anodised finish, gold-plated connections and Superbrite™ blue power indicator, the QX300.4 reflects the styling and engineering of turn-of-the-millennium car audio. Delivering a manufacturer-rated 75W × 4 at 2Ω or 150W × 2 bridged at 4Ω, it combines a PWM MOSFET power supply with Tri-Linear operation and Twin-T bass equalisation. A nostalgic piece of Phoenix Gold's history for collectors and enthusiasts of classic aftermarket audio.

New Old Stock (NOS) condition: Never been installed or used beyond professional testing. Exceptionally well preserved, with only two minor hairline scratches on the top surface. Original packaging is not included.

All OSCA Vintage Series products have been professionally powered-on and functionally bench-tested ✅

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Product details

Advanced Specifications
  • Brand: Phoenix Gold
  • Series: QX Black
  • Model: QX300.4
  • Era: Early 2000s
  • Amplifier Configuration: 4-channel, bridgeable
  • Power at 4Ω Stereo (12.5V): 50W × 4 (IASCA)
  • Power at 4Ω Stereo (14.4V): 60W × 4
  • Power at 2Ω Stereo (14.4V): 75W × 4
  • Power at 4Ω Bridged (14.4V): 150W × 2
  • Total Harmonic Distortion: Less than 0.02%
  • Frequency Response: 20Hz–20kHz (±1dB)
  • Signal-to-Noise Ratio: Greater than 100dB
  • Input Sensitivity: 200mV–4V
  • Adjustable Crossover: 40–800Hz
  • Crossover Slope: 12dB/octave
  • Bass Boost: 0 to +15dB at 45Hz
  • Recommended Fuses: 2 × 20A ATO-style
  • Operating Voltage: 10–15.5V DC
  • Typical Idle Current: Less than 1.5A
  • Chassis Dimensions: 353 × 241 × 51mm
  • Overall Dimensions: 381 × 241 × 51mm
Key Features
  • Black Anodised Finish gives the amplifier its distinctive QX Black Series appearance.
  • Superbrite™ Blue LED provides the classic illuminated power indicator associated with the era.
  • Tri-Linear Technology allows simultaneous stereo and bridged mono operation.
  • Twin-T Bass Equalisation provides adjustable bass boost of up to +15dB at 45Hz.
  • Adjustable Electronic Crossover offers high-pass and low-pass filtering from 40–800Hz.
  • High-Level Input Compatibility allows connection to factory head units without RCA preamp outputs.
OSCA Fun Fact

Back in 2002, the Phoenix Gold QX300.4 was listed at US$299 — equivalent to approximately US$560 today. A glimpse into what enthusiasts were spending on Phoenix Gold equipment over two decades ago.
Phoenix Gold QX300.4 Owners Manual

Phoenix Gold — The QX Era of Car Audio

Around the turn of the millennium, Phoenix Gold's QX range formed part of the brand's expansion beyond its earlier enthusiast-focused amplifier generations. The series appeared in both metallic and black finishes, with the black models particularly remembered by enthusiasts in European and Canadian markets. During an era of custom boot installations, multiple amplifiers and growing interest in powerful aftermarket sound systems, the QX range offered a more accessible entry into Phoenix Gold amplification. Enthusiast discussions years later continued to compare the QX models, their construction and their place within the brand's wider history.

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