Korora preamp & supplier (24v line/battery supply) for MM/MC phono, has adjustable loading & gain but you must open the unit to set the internal switches. Cosmetics are great but I fear something may be wrong like an intermittent connection. When I used this a while ago I heard what sounded like additional cracks/pops (louder then normal) from the record, not continuous but occasional, but the music sounded fine otherwise. Now when I tried it they are gone and it sounds fine? Regardless, I believe it will need repair as these things usually don't go away for good. Sold ASIS and for repair! Was highly rated for it's price of several hundred when new.