The 3124V is a high quality, compact, 4-channel mic preamp. It is equipped with the AP2516 input transformer and the proprietary output transformer found in all API mic pres and throughout the API product line. Additionally, the 3124V offers Variable Output Level Control and switchable 3:1 output transformer selection. The unit has an internal 48-volt phantom power supply, which is switchable for each channel, as well as -20dB pad switches that affect both the mic and Hi-Z instrument inputs, both located on the front panel.