http://www.rockfordfosgate.com/rftech/library/2002/1_Source_Units/MAN4223A_RFX8240-50_Pla_MAN.pdf

Audiophile components throughout
Dual 20-bit Platinum D/A converters
Full copper-plated chassis for superior noise rejection
Platinum finish metal alloy faceplate
Balanced 8V line outputs with dual mini-DIN connectors
Coaxial digital input
Metal alloy rotary encoder knob
Dual preamp outputs with double shielded cables and metal RCA connectors
Low impedance <50 ohms/5V preamp output
24 FM / 12 AM presets with auto memory store
Auxiliary RCA inputs
Backlit LCD display with clock
Switchable red/green illumination color
Mute function
Bass & treble controls +/- 12 dB @ 100 Hz & 10 KHz
100 dB dynamic range / 86 dB channel Separation
No built-in power - outboard amplification required

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