Best Pre for ATC 100's

Second the ATC line of pre-amps.

I used a CA2(the older version) with a pair of the Active 20's and thought it was a great little preamp at the time. Had XLR outputs although it wasn't a truly balanced design, but still sounded great and was reasonably priced.

I don't know what the new versions of these are going for now as prices have increased quite a bit from 7-8 years ago. Tim

Check out
- Boulder
- Soulution

I personally used Boulder 1012 for 5 years and I have extremely happy with Boulder 1012 + ATC active 50/100.

I audit Soulution 720/721 + ATC active 100 and finish the whole piece of Bach 'Mass in B Minor'. So it must be good.

3rd the ATC preamp. They were designed to work with their speakers. I'm not saying nothing else is better, but I don't think there is at the price and with active ATC speakers. They're great on their own, and far better with their speakers IMO.

May I suggest better power cords and a power regenerator, and those parallel power line filters? Those have a humongous difference in the ATCs. They are very very sensitive to this sort of treatment.
Also, plenty of people I know run ATCs with tube preamps and I read online that YBA has the perfect preamps for them as well as the preamps from ATC's own line.