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Balanced Input Circuit Board

This circuit board enables balanced inputs to an unbalanced input amplifier.

It came from a working Hafler PRO 1200 amplifier. You can see it has XLR and 1/4" input jacks. It has its own power supply that takes ~50VDC from the amp's rails and converts it to the ±10VDC to operate its circuit.

Details about this circuit card, board layout, and schematic can be found on pages 9 and 10 here:


How about $25 + postage? Let me know of your interest. Thanks


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