NAD SERIES 20 3020 INTEGRATED AMPLIFIER. For example, the pre-amp out jacks may be connected via a stereo patch cord to any high quality separate power amplifier. To use a separate high power amplifier for your main stereo speakers while continuing to use the nad 3020'S inbuilt power amp for headphones or extension speakers, simply install Y adaptors to split the signal from the pre-amp out jacks.
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