The RPQ503 is the next evolution in AEA's trusted lineage of high-impedance, high-gain preamplifiers. More than just a preamp, the RPQ503 also includes the expanded EQ section of the RPQ3, with boost and cut controls for both low and high end, on custom, compact, dual-concentric potentiometers. Featuring a powerful combination of ultra-low noise, low-distortion op-amps, ultra-high 68KΩ input impedance, and 85dB of clean gain, the RPQ503 delivers exceptional clarity and detail. The RPQ503 was designed to work great on passive ribbon microphones, however, when a preamp works well with a passive ribbon microphone, it will excel on every microphone. At once open, transparent, and musical, the RPQ503 is a versatile tool for the front end of any signal path. The RPQ503 is a powerhouse that provides unparalleled high gain with low-noise. With 85db of clean gain, the RPQ503 gives you enough juice to record soft sources without ever having to worry about noise. The RPQ503 is the tool of choice for all microphones whenever a true and pristine signal path is desired. AEA's 3rd generation circuitry is the cleanest and most musical design we’ve done yet. AEA Gen 3 Preamp Circuitry with our Signature CurveShaper EQ 1-Space 500-Series Preamp Ultra-High 68KΩ Input Impedance 7 to 85 dB of Gain EQ Boost/Cut, +/-20 dB with LF/HF Sweepable Frequency Polarity Switch Mic/Line Input Switching Made in the USA