Audio Research for Sonus Faber Extrema

Hi All,

I'd like to advice you for nice PRE for my beloved Extrema,
Right now I'm running them with Meridian 502 and Power 557 but something is missing.
I thought about Tube based PRE , and got many good feedbacks for Audio research but I'm not sure which is good for me.
good chance i'll update the power also ( guess it will be SS or classD) but i want to start with the PRE .
Please advice , My budget is about 1500 (Used).

Feel free to email me...

Thanks all!