Which Pre-Amp Pass Labs or Audio Research

Well, most recently I tried used AR LS17SE and Pass XP-10 at home for extended listening. From a system matching standpont, the XP-10 was better to these old ears, but your mileage may vary. Have owned several AR pieces (SS and Tube) and they make great gear.....so does Pass though.

I have owned the Pass XP-20 as well ARC Anniversary Ref 40. Very, very different sounding and you'll hear that difference immediately. It's hard to say which you would prefer as you don't say why you are dissatisfied with your current sound and what type of music you listen to primarily. Help us out please.

Barrysandy, I think I`ll have a much better match pass to pass. I also want to try S/S for a while after a few years or thousands of hours down the road its time to change tubes, don`t have to worry about that with S/S. My taste in music is classical,Jazz,blues, gospell

I posted a response in my system description but here are some further thoughts. I don't think tube usage would be an issue with the Ref5 unless you leave the preamp on all the time. My Ref40 warms up in an hour and doesn't sound much better after that. The signal tubes will easily last 5000 hours and are not that expensive.

If set on Pass, read the description of the Xp-20 v. Xp-30 here at dagogo:

http://dagogo.com/pass-labs-xp-30-preamplifier-review

The XP-30 would be my choice if you wanted to go with the Pass preamp.

As another less expensive option, I don't know whether you have tried different tubes in the LS22?

I also found this article of interest. I have tried these specific types of mods in other equipment with terrific sonic results but few people have the skill or want to damage the resale value of their stuff:

http://www.10audio.com/arc_ls22.htm

Good luck!

Are you using the old 350? not a .5 serie?