The Arkiv B has an output voltage of .4mV and the Titan has an output voltage of .5mV.
If you still have the ARC Ref Phono, the ARC database says it has adjustable gain of 48dB or 69dB. If your unit is set at 48dB, try switching it to the higher gain - rear panel switch(?). The higher setting will yield plenty of gain for the Titan; try it with the Arkiv B and see how it sounds.
Gain on the Ref3 linestage varies by 6dB based on whether you're using balanced (higher gain) or single-ended cables to your amp. If you're currently single-ended, see if you can borrow a set of balanced cables to hear if the increase in gain brings satisfaction.
If your Ref Phono is set at the lower gain and you're using single-ended cables off the Ref3, then I can see where you'd *really* have to crank it. :-)
Good luck,
Tim