Peter I just read the manual for this preamp. It is supposed to have a 24v DC power supply to power the device. The power supply jack is the small one on the rear. It also can provide 24v phantom power available at the XLR socket on the input. There is a button on the rear that turns on this phantom power. There are 3 types of phantom power specs which are 48v, 24v, 12v. The 24v is not a very popular one at all. What you would usually plug in here is a condenser mic with the phantom power turned on. This should work ok for even 48v models. Might try it on a inexpensive condenser first though.

Below is from your user manual.

Use of 24V- rsp. 48V-Phantom-Power
(Phantom power = remote supply, here: powering an audio device via the connected audio line) Turn on the phantom power only if the unit connected to the XLR socket is designed to handle it! In general, suitable units are e.g. condenser microphones, active DI boxes and other special audio devices, whose power supply is drawn from the phantom power. Such devices are also labelled accordingly; please heed the permissible power consumption (max.10mA). High-quality dynamic microphones with a balanced signal need no phantom power, but can handle it anyway. Other devices which have not been designed explicitly for phantom power operation can suffer from considerable malfunctions, and damage may result as well. Examples of devices that may be damaged by incorrect application of phantom power include: Low-cost dynamic microphones with a mono jack plug (unbalanced signal) that were fitted afterwards with an XLR connector. Audio devices with a balanced XLR output (e.g. DI boxes, effects devices, instrument preamps with a DI output etc.) which are not protected against phantom power applied to their XLR output. (The DI connectors on AER products are protected against applied phantom power.) Other audio devices (such as preamps, effects pedals etc.) whose unbalanced line output was replaced by an XLR socket. If in doubt please consult the manufacturer of the device you are using.

Last edited by Brian Hughes; 01/28/16 04:59 PM.
BIAB 2024 Ultrapack- Studio One Pro 6.5 Windows 10