Carver Amazing Platinum Mark IV

Any opinion bad or good thanks Marjan
I owned a pair for a number of years. Stock version. No mods. They are excellent speakers. The ribbons, obviously, must be functioning properly to sound their best. If they start buzzing then look out. Also add some mass to the base of the speaker and put a tube preamp in front of a very high power amp. Carver amps? Maybe. I would say more like a Pass 350.5....
I own a pair of the original Carver Amazing Loudspeakers.
I love them. Excellent sounding speakers, if you have the amplification.
Much better bass and highs than my Magnaplanar MMG's and less colored through the mids.
Two biggest contentions about those is the expensive amplifier requirements for relatively inexpensive speakers and the open baffle, high Q bass drivers which were, let's say, ahead of the technology.
I friend of mine had these for quite some time so I got to hear them a lot. At one point his girlfriend really put some pressure on him to get them out of the living room, so he had to look for replacements that were smaller and more 'appealing'.

I suggested a set of speakers made by Audiokinesis, as they are easily driven by his amps (tubes) and were a lot smaller. Surprise! -not only were they smaller and easier to drive, they also sounded better in every way! Better imaging, better bass that went deeper, more detail. He was ecstatic.