The Marantz PMD 661, MKII & MKIII Concert MOD upgrade rebuilds the XLR inputs using high speed, low noise and very low distortion op amps that dramatically improve fine detail and clarity. The result is a very detailed, open 3D soundstage. Components are selected by ear to optimize detail and imaging for recording all types of music where transparency is needed.
Please note this upgrade works in all 661 versions.
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