I have acquired part of a Magix Audio Cleaning Lab 12 XXL.  
This includes a preamplifier - but no power supply.  Three questions:
1  What current rating (ma) is required from a 9v mains power supply for this preamp - is it 300ma?
2  I believe that the polarity of the 3.5mm jack plug from a mains power supply should be "Tip positive and Sleeve negative".  Is that correct?
3  What equalisation does this preamp provide - is it for moving magnet or for moving coil pickups - or none at all?