phono stage volume

Assuming the Hafler already has a phono stage, just turn up the volume. What you describe is not uncommon.

Cford- As others have noted, just turn up the volume. The volume pot in the Hafler is rather inexpensive, so the higher the volume control position, the less it's in the signal path. I wouldn't recommend a stepup transformer or pre-preamp with your cartridge. If you enjoy the sound and the noise floor is acceptable, then don't worry about the volume control position. Enjoy the music!

Grado cartridges are not moving coil nor moving magnet; they're a hybrid design known as moving iron, basically a variable reluctance generator design. Some of their models are available with different-level output options, low, medium, high. Don't know what your X+ is set up for; give them a call to find out. You might be able to get a different model that's more suitable to fit your existing equipment.

I don't think the problem is the cartridge. I put in my old Audio Techica cartridge and its level is about the same. I think its the 34dB gain of the phono input to the Halfer. Any way to increase its gain?

Just turn it up. Unless you're past 1 o'clock on the volume, I wouldn't even begin to worry about it. On CD, I typically run at about 9-10 o'clock; with vinyl it's always between 11 & 12, sometimes more.