Have Luxman 509x. Considering Pass Labs INT-250 or Dan D’Agostino Progression Integrated

Hegel and save a bundle. :) 

Funny how we all hear different. I have owned the Pass 60 and I now own a Pass 250 and neither sounded mechanical. My 60 sounded very warm and smooth. My 250 is less warm and more articulate and refined in the treble compared to the 60. 

Funny how we all hear different. I have owned the Pass 60 and I now own a Pass 250 and neither sounded mechanical.

True, and personally I am OK with that.  I just felt these amps needed to be hears by the purchaser, really ANY amp should be.  Also, I may have mentioned, this may very well be speaker dependent.  I've heard from some objective owners of Pass that they had very different experiences with different speakers, so it absolutely pays, IMHO to think of whether or not to buy a pass to think of them as part of a system rather than standalone units.

I am using the Pass Labs X250.8 monos.  Love the sound.  A few things I found using these amps that improve on their already great sound are: 1) Better power cords.  Don’t skimp on power cords.  They will be expensive but worth it.  2) Dedicated power lines.  3) I isolated the amps from the floor using springs.  The amps sit on four 48 lb/in springs making the Fn= 3.6 Hz, if I recall correctly.  Big improvement in sound.  Detail increased by quite a bit.  The overall sound improved.  4)  Added a patch of constrained layer damping material on the inside of the top cover.  Primarily I didn’t like the clangy sound when tapping the top cover and the damping material took care of that.  What I didn’t expect was another improvement in the sound.  I find the Pass Amps respond very well to better Power, Speaker and Interconnect cables.  Buying cables is not as fun as buying a new amp or speakers but the right synergy can be very satisfying.

I have not heard any other amp in my current system so I cannot judge what would or could be better.  I have heard my speakers in a store with the Dan A amps and they sound really good too; but that was before my tweaks.

@tonywinga 

+1 I used to have Pass and moved to Audio Research… doing exactly what you did. Yep, don’t cheap out on power cords and isolation steps can provide further improvements. I’m using springs now… I’ll probably spring for Townsend or Silent Running Audio platforms at some point.