AEA RPQ503

Preamplifier optimized for ribbon microphones with 2-band EQ - 500 Series format

• 500 Series preamp designed specifically for ribbon and dynamic microphones
• Third-generation AEA circuit derived from the renowned RPQ3
• Gain up to 85 dB with extremely low noise
• Ultra-high input impedance of 68 kΩ for maximum sonic transparency
• Two-band equalizer with boost and cut up to ±20 dB
• Adjustable LF and HF frequencies with dedicated concentric controls
• Selectable microphone and line inputs, +48 V phantom power, and polarity reversal
• Designed and built in the United States

The AEA RPQ503 brings all the sound quality of the renowned RPQ3 to the 500 Series format, offering a professional preamp designed to get the most out of ribbon microphones, while also delivering excellent performance with dynamic and condenser microphones.

Thanks to the AEA Gen 3 circuit, the extremely high input impedance of 68 kΩ, the maximum gain of 85 dB, and the ultra-low-noise operational amplifiers, the RPQ503 delivers an extremely open, natural, and detailed sound, fully preserving the character of the connected microphone.

Professional Preamplification for Ribbon Microphones

The high input impedance is one of the RPQ503’s key strengths. With phantom power turned off, the 68 kΩ load allows passive ribbon microphones to operate under optimal conditions, keeping the original frequency response and dynamics intact.

The gain range of 7 to 85 dB also allows even the quietest sources to be amplified with ease, while maintaining extremely low background noise.

Advanced CurveShaper™ Equalizer

The RPQ503 incorporates the latest evolution of AEA’s renowned CurveShaper™ circuit with two fully adjustable equalization bands. Both allow for boost or cut adjustments of up to ±20 dB, while always maintaining a musical and natural response even with very pronounced settings.

The cutoff frequencies are continuously adjustable from 40 Hz to 675 Hz for the LF section and from 2 kHz to 28 kHz for the HF section. The equalizer can be completely bypassed from the audio signal path, and each band can be easily reset to neutral using the mechanical center position of the gain controls.

Maximum Versatility in the 500 Series Format

In addition to the microphone input, the RPQ503 features a selectable line input that bypasses the microphone preamp when needed. It also includes +48 V phantom power, polarity reversal, and three-level LED indicators for signal monitoring.

AEA Sound Quality for Any Audio Chain

Transparent, dynamic, and incredibly quiet, the AEA RPQ503 is the ideal choice for recording studios, broadcast facilities, and music production environments seeking a reference-quality 500 Series preamp capable of bringing out the best in ribbon, dynamic, and condenser microphones with impeccable sound quality.

Professional performance in a single 500 Series slot

Compact yet extremely feature-rich, the RPQ503 combines top-tier preamplification and musical equalization in a single 500 Series module, offering a professional solution for any recording chain.

Technical Specifications

• Format: 1-slot Series 500 module
• AEA Gen 3 circuit derived from the RPQ3
• Gain: +7 dB to +85 dB
• Input impedance: 68 kΩ (phantom power off)
• Input impedance with phantom power on: 11.3 kΩ
• Output impedance: 50 Ω
• Maximum input level: +20 dBu (minimum gain)
• Maximum output level: +27 dBu into a 600 Ω load
• EIN:
  • -130 dBu typical (40 Ω source)
  • -128 dBu typical (150 Ω source)
• THD+N: 0.0018% (1 kHz, 22 Hz–22 kHz, 30 dB gain)
• Frequency Response:
  • 30 dB Gain: 10 Hz (-0.6 dB) – 160 kHz (-3 dB)
  • 85 dB Gain: 10 Hz – 160 kHz (-3 dB)
• CurveShaper™ Equalizer:
  • 2 shelving bands
  • Boost/Cut ±20 dB
  • Variable LF: 40 Hz – 675 Hz
  • Variable HF: 2 kHz – 28 kHz
  • Dedicated EQ bypass
• +48 V Phantom Power
• Selectable Mic/Line input
• Polarity reversal switch
• LED indicators:
  • Green: -20 dBu
  • Yellow: 0 dBu
  • Red: +20 dBu (clips at +27 dBu)
• Anodized aluminum front panel
• Dimensions: 3.8 × 17.27 × 13.34 cm
• Weight: 338 g
• Designed and manufactured in the United States