Disappointment with Pass Labs - I'm looking for something else

Hello, I am new to this forum and my mother tongue is not English, so please forgive me if I make mistakes as I use a translator.

I recently bought an XA30.8 and an XP12. I was very happy but as time went by I began to not feel comfortable with the sound.
After doing many tests, I find that the XA30.8 sounds very very sweet but actually too much. I find it to be a loosely defined amp, somewhat muddy and lacks a lot of air and grip. The soundstage is very closed.

The XP-12 is the worst of the two. It is a previous that removes a lot of resolution and information, without transient attacks and sunken mid frequencies. Instead it brings warmth.

Has anyone of you found the same?

If you ask me, I have a Klipsch Cornwall and a dCS BArtok.

Now I want a capable amp, forceful, something warm, decisive, airy and with a great soundstage.

At first I thought of changing my XA30.8 for X250.8, and changing the XP-12 for a second-hand Audio Research Ref5. I am afraid of this change and continue with Pass, since I can go back to the same thing a bit.

On the other hand I have thought of going for a Luxman 900 combo, since it has very good reviews and from what I have read it could be the winning ticket.
Dear @opm :  I agree with all those owners/gentlemans that touted Pass electronics because N.Pass designer is second to none.  I knew N.Pass rigth when he owned/designer too Threshold and his amps were and even today are still very good vintage performers-

Here you have several advices mainly to go with the Pass 25 and the 22.

Real problem belongs not to those great Pass electronics or the great Bartok unit but to the self speaker limitations been horn design and with a woofer developing heavy/high
 InterModulationDistortion levels that made that increment the speaker TotalHarmonicDistortions. Your ekectronics including the dcs unit are in other league where those speakers are truly short.

So, i agree with the gentleman that said change those speakers, he is rigth. Pass is no trouble..

The ones that siad here that the problem can be " fixed " with tubes and changing the stock unit tubes to " tailored " your needs are only telling you to add distortions to " colored " the sound reproduction instead to fix the real problem that has a name: speakers. Horns almost never can honor MUSIC. These kind of tube units advises could be too because your speakers has a sensitivbity over 100db and then according them you need 10watts or lower and a SS over say " 100 watts " will not works and this is a total misunderstanding because we can run high sensitivity speakers with 300 watts or even higher SS designs.

The " problem " with good SS eltectronics designs as Pass is that any kind of system audio items that's not up to the task can't be stays " hidden " behind the colored/high distortions developed by lesser design electronics. In this case your speakers.

If you take a look to the audio market the higher number of audio items  belongs to speakers one.

Do it a favor and change it, put on sale ( always exist horn lovers. ) and you will get what you are looking for with the same electronics you own today.

Regards and enjoy the MUSIC NOT DISTORTIONS,
I have the Klipsch Forte III.  I also have the Pass 30.8 and a DCS Rossini DAC.  I really do like the 30.8 amp, it's great with other speakers but I don't like it with the Klipsch.  Personally I far and away prefer the Decware Zen Triode 2.5 watt tube amp.  Better everything with the Forte III.  I'm thinking of jumping up to the even more efficient Cornwall IV like you have.  I love the 30.8 on the Maggie LRS, it's like a different amp but something leaves me cold with the Klipsch.  

Did you ever try your Bartok direct to the amp?  The Decware amp has two inputs and an attenuator so it's sort of an integrated amp if you need more than one input.  The sound is beautiful, great bass and so fatigue free and extended at the same time.  Fatigue is one word I would use to describe the 30.8 with the Klipsch speakers.  For 1000 USD new the Decware Zen triode is an amazing hifi bargain that amp competes with anything I've ever heard before.  
I recently tried a Xp12 and also found it tame, polite, un-dynamic.  I paired it with my Pass XA25 and Cornwalls.  I just got a LTA MZ3 and boy what a difference! Much more dynamic, engaging, possibly more resolving, better bass.  My opinion would be to try new preamp first, I’ve never heard anyone describe the 30.8 like you did.  I didn’t think the Cornwalls could be tame and in-dynamic, but that what the xp12 did, I was shocked.  Of course my system, my room, my ears.
I am a long time Pass fan. I bought a Threshold 250 watt amp in ~ 1980 A T2 preamp shortly thereafter, then a Pass x350 for 15 years. He does outstanding amp design and good preamps (not to my taste now). 
But from what you are saying about your tastes the Audio research preamp sounds like a great match. Your tastes sound like mine.  I owned a Audio Research REF 5SE for years, I now have a REF 6SE. The REF / Pass 350s is a good combination and would be better than the amp you have now.The speakers unfortunately are probably the real problem. The amp could be great depending on speakers. Not sure what your price range is, but you need some accurate high end speakers, B&W, Wilson, Sonus Faber, the choices are endless, I would stay mainstream then there are lots of reviews. Over the last 50 years I migrated from a mixture of components to All Audio Research Components and Sonus Faber Amati Traditional speakers, and an Aurender WE20se streamer. 
After reading my rambling post. I think my recommendation would be to get a set of high-end speakers... then assess your system sound. Put some serious effort into finding speakers to fit your musical taste. What music do you like? If it is punch dominated then B&W is a good choice. If you really like imaging maybe Wilson. If highly varied, with classical and acoustic then Sonos Faber...I recommend whole heartedly Olympica or higher.