How do I smooth out violins?

A number of good responses above, including your own regarding changing tubes. I have experienced some dramatic benefits from this in my system. As someone else hints at above, finding ways to lay back the sound is most desirable. I used to favor a more forward presentation, but the desire for a more relaxing, listenable sound changed that. A caveat, though, mirroring what someone else indicates above,is that some recordings of violin are too closely miked and/or poorly made, and as such might be immune to virtually any kinds of alterations in one's system. An example(at least in my experience)is David Oistrakh's performance of the Beethoven Violin Concerto with Andre Cluytens on Angel. Also, in general, I have always found the blue label Angel classical recordings to be somewhat bright. Aside from Cardas, you also might want to consider one of the lower priced Purist Audio cables,e.g.Musaeus.

I think there are a lot of good comments above. I am especially appreciative and supportive of where frogman was going, in that you really want to diagnose and address the problem rather than throw bandaids at it. Who among us appreciates the auto mechanic who fixes our cars by sequentially replacing parts until the problem goes away?

When I read the OPs comments, I focused more on lack of integration than lack of smoothness. I think most of you focused on smoothness rather than integration. This is where the comment above that this may be due to more than one issue is also relevant. Further clarification from the OP is required with respect to what he means by "smoothness." Does this mean you are experiencing excessive grain or excessive brightness? If it is excessive grain, I strongly urge you to replace the aq4s. They are very grainy, but I did not find them overly bright. If the problem is brightness, then some of the comments regarding power treatment and IC's may well be relevant to this problem. If dirty power is exacerbating the problem, it will probably be variable. Most people have cleaner power in the evening than during the day. If the problem is not variable, you may not want to address power treatment first.

My guess remains that the "integration" (coherence) problem is speaker related. I have no knowledge of this speaker. If those who do can indicate that coherence is a strong point with this speaker, well, I guess the problem must lie elsewhere. I can tell you this. I had major issues with integration (lack of coherence) and also a minor issue with stridency or harshness in reproduction of violins (at the crossover frequency) that pretty much completely went away when I went from Magnepan 1.6QRs to 3.7Rs. I have an extensive library of orchestral and chamber music, and I would have to go back to cds recorded in the early 80's to find examples of recordings where the violins are excessively bright. Granted, certain recordings can make a violin sound larger than life due to close miking, which I suppose could be a part of the problem here. But I find it difficult to believe that the OP has somehow managed to selectively collect a large number of bad recordings.
I do have a tubed CD player, but I do not have a tubed pre amp. I have nothing against tubed preamps, but they are not a panacea, nor is vinyl. Digital can get this right, and will not require investing in a top notch vinyl rig and phono preamp. Resorting to vinyl is not really a viable option for those who have a substantial investment in CD's, and I would suggest most fans of classical would not be satisfied with the quantity of music that is available on vinyl as compared to digital.
One other possible issue here is jitter. I don't know the Marantz, but in my experience jitter will for some reason manifest itself as most objectionable with music that is rich in high frequencies.

"Trying to find recordings that sound good with your system does`nt make sense". It makes plenty of sense.How can you judge the sound quality and characteristics of your system without using a known recording to evaluate its reproduction and possible deviations?

Improving the quality of AC power is`nt a "band aid" but is fundamental and all components benefit from better electricity quality.Immediately jumping in and changing compenets is`nt addressing the root cause. A good recording of massed strings needs to be listened to in order to determine if the problem is simply source material(bad recording causing the harshness) or a component it self.
Regards,

Correct....it's mostly the preamp. A Manley Shrimp or Jumbo would definitively help. Love the Spendors and McCormick, Marantz could be better, AQ Type 4 is a bit thin, AQ Type 6 is warmer. Signal Cable is really good stuff for the money.

I second Frogman's very well put comments, as well as the recording-related comments by Rok2id, Mapman, Charles1dad, and Opus88.

If you don't feel certain at this point as to the degree to which the problem may be the result of deficiencies in the recordings, such as heavy multi-miking and excessive processing, my suggestion is that you can resolve all doubt by investing in a copy of Chesky CD31, featuring Dvorak's "New World Symphony," Jascha Horenstein conducting the Royal Philharmonic.

It is unfortunately out of print, but is available from various sellers at highish prices. It is the best sounding CD of a symphony I have ever heard (although most of the orchestral recordings in my collection are on vinyl), notwithstanding the fact that it was recorded in 1962. Great music and a fabulous performance as well!

Regards,
-- Al