Rolls mp13+ecm8000 - not much signal

[Jman]

I can't seem to get enough signal from this combo. When I try the ecm8000 directly into my Mbox it's fine. If I use an SM57 mic via XLR or a logitech headset via 1/8" with the rolls pre, those are both fine. But together, even with the gain cranked and phantom power on, lots of noise and not enough signal.

If I do "check levels" in REW, it complains the signal is too low.

Any ideas?

Edit- looking around the net I've found that the Rolls only puts out 12V on phantom. The ecm8000 needs 15V. My Mbox probably puts out more and that could be the problem. Not a very good mic pre if so.

[DrWho]

Yea, the ECM8000 isn't gonna work with only 12V.

[Jman]

I mis-read the Rolls website, the schematic claims 21V phantom. I'll measure it at a friends place this week. If it is putting out 21V, then I have no idea why the Rolls doesn't work where my Mbox does.

[Jman]

5.2V of phantom power. Nothing like paying $60 for a box with 2 functions and 1 of them doesn't work. I'm waiting for a reply from Rolls now.