Phono Preamplifiers In The Test: Tips And The Best Devices At A Glance Do you have an equalizer preamplifier? If so, you will quickly notice that your new turntable, if you connect it to your amplifier, will produce nothing but a quiet hum. Why? Because turntable cartridges work with an extremely low output voltage and this must be amplified accordingly. If your amplifier does not have an input labeled with: Phono MM MC then there is a good chance that you will have to buy a phono preamplifier. This problem often occurs because the manufacturers of amplifiers didn’t count on