AKG K612 Pro open monitor headphones. No problems with operation.
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The serial number of the headphones is 01062. That is, headphones from the very first series (serial numbers start from 01000, that is, 62 pairs out of about 10000), which are the most valuable, with a large number of low frequencies.
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1959 - World's first supraaural, open-back, lightweight headphones, with superior sound quality. Therefore I think that the jack itself needs rewiring, or taking apart and cleaning. The jack is quite uncomplicated and designed to be disassembled and cleaned.
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Sound just as good as when I first bought it.
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Bought these a couple of years ago plugged them in once not used them since so really are as good as new, if you are after a pair of these headphones these are a bargain.
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In good condition, comes with iriginal box.
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2x 3-pin XLR Male Balanced to 4-pin XLR Female Balanced Headphone Audio adapter. Connector: 2x 3-pin XLR Male Balanced ,4-pin XLR Balanced Female.
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