Preamp for Pass


I have a ARC LS26 preamp, but thinking about trying something else, but still a tube preamp.

I have tryed the DIY Tram II witch was fitted with duelund compoens and others opgrades. that sounded great from the midrange and up, but lacked some in the bass, compared to my LS26.

So witch tube preamps are great with Pass?
pierre1976