Classe vs Moon audio vs Ayre vs Pass


These all seem to be highly regarded amps. Does anyone have an opinion about the strengths and weaknesses of these amps and your reasons for choosing one of them if you decided to buy one.
Thanks
ecka
I can only give you my feedback regarding Simaudio Moon and Ayre. I have not used Classe or Pass in my system. I have also used Arcam, Rotel, and Parasound amps.

I use a Monarchy tube DAC with DIP as a front end. Speakers are Green Mountain GMA. All interconnects are DIY magnet wire as are the speaker cables. I listen to a pretty wide variety of music with a lot of jazz, classical and acoustic guitar, piano.

I tried the Simaudio I.5 and now have an Ayre AX7e (see my review under "reviews"). For me, there was no comparison. I tried the I.5 with multiple cables and interconnects and simply could not tolerate the sound. It was precise to the point of being analytical and cold. Instrument timbre seemed coarse and harsh with a high degree of listening fatique. The Ayre by comparison has been the best integrated amp I have heard to date and is in my system to stay. Musical timbre is faithfully produced, instrument separation and placement is amazing without sounding analytic. On top of that, Ayre has some of the best support out there.

I went through 5 amps in two years and wouldn't even think about changing this one.
probably more like praise of ayre than comparison to others, but i lusted after a W-7 simaudio for awhile, only demo at the dealer. thought the sound was awsome at the dealer, but ayre had also been on my short list, about a 2 months ago ended up with a V-5xe. happy as can be and im not looking back. its pushing a pair of sonus cremonas, better soundstage, more detail, im sure theres
better out there , but for my system and my budget, couldnt be more satisfied.
I only have experience with Classe vs Ayre; Ayre wins easily. & what Dre said: Charles Hansen really does support his products.
I have owned Ayre and Pass Labs. They cater to the same genre of sound. The Pass XA60.5 monos cost twice as much as the Ayre V5xe, so this is probably not a fair comparison. Be that as a disclaimer, I do prefer the Pass. Some might say that the upper frequency extension for Ayre is better. To me, class A amp. such as the XA60.5 definitely has fuller body, more detail, and the mid range is much more natural. Now unlike typical complaint about class A amp., the XA60.5s do not lack that last octave of the upper frequency at all. After listen to them for some time, I've come to realize that the artificial top end in so many class A/B amplifiers is what cause harshness and electronic sounding. It also makes the music more aggressive than what it naturally is, thus my ears got tired after a while. So Pass does it just right.
I own a Classé CA-2100 feeding a pair of Oskar Kithara (4 ohms with Heil tweeters). When I bought it in 2006, the other amp in the room to compare with was the Ayre v5xe which costs 1000$ more (at the time). I found that the Ayre was an easy listening unit but did not feel anything special about it. Overall it sounded good but no single voices or instruments were ever coming through the bulk. I remember that it showed confusion on some heavy orchestral music like Beethoven 10th.

On that same music, the Classé resolution was clearly superior. The sound was a touch more forward but I found the focus on solo parts very interesting. Also noticable, from one CD to the next, it was like replacing the whole sound system. That amp is neutral.