Which Pre-Amp Pass Labs or Audio Research

I have been using a PASS X250 and now X25.5, I originally had it with a passive preamp and it worked fine, then I wanted to try tubes bought a Audio Research SP16. Boy was I disappointed. Kept it about a month then bought a matching PASS X2.5 preamp running balanced and it was an eye opening experience.

My advice get the PASS preamp, you wont regret it!

It all depends what type of sound you like. Pass is clean and timbre-accurate and very neutral.

AR has tubes and adds harmonics and bloom but timbre isn't accurate - it has more of a whitish sound, but beautiful just the same.

Personally I prefer the Pass but it's a matter of taste - apples vs oranges. Both are excellent.

"AR has tubes and adds harmonics and bloom but timbre isn't accurate - it has more of a whitish sound, but beautiful just the same."

How do you know the timbre isn't accurate on the AR? As far as I know, there's no way to measure timbre.