Pass XA Monoblock Amps with Audio Research Preamps

A tubed preamp can be a rewarding combination with your amp. I've seen definitive statements on this website that:

1) AR Ref preamps are not a good match with Pass XA.5 series.

2) AR Ref preamps are a great match with Pass XA.5 series.

My interpretation would be to proceed cautiously and critically, and seek a price where you could resell if the sound was not superior in all regards. Do not accept mushy bass or a rolled treble for some midrange bloom.

I do think it is important to use the balanced connection on the amps. I would be reluctant to use a tubed preamp that people charactarize as smooth and musical. Not that those types of preamps are bad, but they may be too much of a 'good' thing with the Pass. My opinion would be to seek a highly resolving preamp with good frequency extension.

I can give a firm recommendation that the BAT Rex and Pass XA.5 is a great combination. Really, really.

If the input impedance of the amp is less than 30K, ARC preamps will tend to be bass-shy. There was a thread about this just a few months ago.

At this point, I am considering the Audio Research LS-27 along with the Pass XP-20 as preamp possibilities. Some of the people who have suggested the Pass XP-20 have told me that I would get tube-like sound without the maintainance of tubes. Other reviews I have read about the Pass indicate it is on the neutral side. I would think that the Audio Research LS-27 would effect my system with much more of a tube like sound and the Pass might be better in the bass area but without hearing either of them, its just speculation.

I tend to think both would be a good match with the Pass XA100.5 Monos that I own.