Mark Levinson No.523 Dual-Monaural Pre-Amplifier The Mark Levinson № 523 is the definitive preamplifier for the analog music lover. Six line-level analog and phono inputs travel through the Mark Levinson proprietary Pure Path discrete, direct-coupled, fully balanced, dual-monaural signal path for breathtaking purity and performance. With precision control including a discrete, balanced R-2R Ladder volume control, class-A Pure Phono stage, and class-A Main Drive Headphone output, the № 523 preamplifier delivers an uncompromising performance regardless of analog source. Housed in a 6000-series aluminum chassis, like all Mark Levinson equipment, the № 523 is designed and handcrafted in the USA. Product Highlights: Line stage gain, normal gain setting 13.5dB balanced; 7.5dB single-ended Line stage frequency response, 20Hz to 20kHz ±0.02dB Line stage frequency response, 0.4Hz to 370kHz +0.1 / -3dB THD+N @ 1kHz (2VRMS single-ended or 4VRMS balanced output) 115dB @ 1kHz Crosstalk @ 1kHz 115dB