what is difference of klipsch cornwall II & mkII ?

From everything I've seen on the web,they are basically the same.I could be wrong,have been before.Manufacture dates were between 1985 and 1990.Prices ranged from $1650 to $1800 during those years.Go to the Klipsch Community website to get the best info.

I believe the original Cornwalls were made up until 1985, then the Cornwall II's were made until the early 90's, I think. Now they have the Cornwall III's, which are much more expensive. Don't think there is any difference between Cornwall II and Cornwall Mk II. I own a pair of Cornwall II's, from the first year of their production. They are great speakers. They usually go used (depending on their condition, of course) anywhere between $600 and $1500. I think in the last year or so they have averaged between $900 and $1200 on this site.

The original Cornwalls, and Klipsch Heritage speakers were constructed from cabinet grade plywood (much better than the crap Home Depot sells). I believe the current Klipsch Heritage models that are still being made (Khorn, LaScala and Cornwall) are built with MDF and are slightly heavier. The drivers have changed over the years, as have the Crossover (parts and design). The older midrange horns used to be made from metal and are now made from plastic. The original Cornwall was probably made entirely in the USA. The new Klipsch is outsourced, probably from various countries - I bought a replacement driver for an older Klipsch and the replacement was made in Mexico. How does all that effect the sound? I have no opinion as I only have experience with the older Klipsch Hertitage speakers. Check over on the Klipsch forums. If I were choosing for myself, I'd buy an older one and tweak it out. They're wonderful speakers for the money and with the right amplification, especially with a bit of tweaking and parts replacement.

Thank everybody
Are they good in fast,complex music so ?
Or what about Dynamic & Separation ?

You will not get better dynamics, both loud and soft, than with horn speakers, this is one of their greatest virtues. They also image and soundstage very well, and are good for any type of music. There is a thread probably about a month old or more on the high efficiency asylum where many different people wrote about why they consider horns the best speaker type. I would suggest looking that one up - I'm not good at providing links, etc., so I won't try.

is Heresy so far from Cornwall ?
& What is the original price of Heresy ?
I think they sell new of it about $700 ?
The terminal of Heresy seems very tiny & may be week!

The Heresy is a significantly smaller speaker. The volume of the box is about 1/3 of that of the Cornwall (that's a guess). The midrange horn in the Cornwall is larger, as is the forward firing woofer. The horn drivers themselves are similar to those used in the Heresy. The crossover is different to accommodate the different designs. The Heresy will not give you the low end extension of the Cornwall, but is a fun speaker in its own right. The Terminals of any of the older Klipsch Heritage series left a lot to be desired from a design standpoint when compared to modern speakers. At one point I think they used simple screw terminals. There's nothing wrong with that unless you need to have something that accommodates spades or bananas. They're very easy to swap out with something more beefy if you care to do a bit of work on them. Left as-is, they get the job done, and deliver the sonic goods when paired up with the right amp/system...big bang for the buck. Paul Klipsch's goal, or a good part of it, was to make high-end performance affordable to most people. If you are seeking speakers with immaculate finish and all the nice bits and pieces to be machined and refined you are probably barking up the wrong tree. The brand new versions that Klipsch is pushing, that are held over from the Heritage line, probably conform a bit better to modern audiophile expectations in this regard, but I wonder if the performance is any better, or worse than their predecessors.