I'm using a Shelter 501 II with a CAT SL1 Mark III loaded with the 100 ohm plugs, with PLENTY of gain! In fact, I keep the volume on my Berning amp around 2:00-3:00, instead of all the way up, because if I leave it up there's too much gain to get sufficient low volume control via the pre. I'd be curious to hear what difference I get using a step-up vs. current setup, but it really doesn't seem necessary. Must admit that some of the previous posts surprise me, especially Bombaywalla's comment on lack of bass. In my room bass performance measures well. I certainly don't doubt his experience, as Bombaywalla has been a helpful & knowledgeable friend, but my rig certainly has plenty of gain w/o noise. Cheers,
Spencer
Spencer