Tubeyist sounding Pre-amp?

What are you trying to fix? I see you have Magnepans, so I'm guessing the highs are too much for you. If this is the case, call Magnepan and ask for some of the resistors that attach to your binding posts. The resistors roll the high's off to take away the edge. Its a problem they know about, and they won't charge you for them. 

Do yourself a favor and sent the Sonic Frontiers back to the manufacturer, at least for an estimate.   They will use replacement components that will not degrade the unit's performance.   Just getting the piece operational should not be the goal.

randy-11

Ok I am going to go out on a limb here. You Sunfire Cinema Grand sound like crap and you are trying to mediate that sound. May not be necessary. I have never sold/owned maggies but sure there are plenty of threads here on the best amps to drive them. maybe an integrated? 
Do you 5 channels? Does anyone need 5 channels? 

no, the Sunfire sounds very nice

I have 2 channels and bi-amp the Maggies

Have you considered the Sunfire tube pre ?Should have synergy with your amp . Had one for a minute and moved on for the fact it was tubey . Have come to the conclusion tubes just aren't my thing no matter how many times i read get a tube pre and solid state amp .