Modwright LS/PS 36.5 or Pass Labs XP-20?

I hope you picked the Pass. A contrarian, I feel solid state phono and line amplification upstream from tube mono blocks preferably in balanced mode brings out the best sound, the quietest noise levels. I know nothing about Modwright but Pass is a real company. Their service technicians rotate as designers so you have great support. 

ivanj, Modwright is a real company as well and makes very good components

Why not look at Rogue as well? I own both Pass and ModWright and they're both real companies; that's some funny stuff there... just saying. Both are great conpanies and it's not uncommon when you call either, you're talking to the men themselves. You can't go wrong with either brand. Best to try both in your system and not take any advice from others. Good luck.

From what I have read on their web site Rogue is a solid, venerable, engineering company with good resumes, good product, a good balance sheet, and offer very good values. I have a colleague who recommends their amps over the high, high priced tube amps (not the OTLs) to drive various electrostats with good results. I merely stated my preference in putting solid state gear by (Pass) in the front of the chain and using valve amplification, such as Rogue, if that is your taste. If you like Rogue preamps that is your good taste. I shall look into Modwright when time permits.  Thanks for the tip, adg101, and I'm glad you got a kick out of my remarks.  Remember Harvey Rosenberg?