How do I smooth out violins?

I will also support the idea of getting power conditioning and better power cords. After that I think you need better cables and CD player for classical music......

IMO, you should decide on one of two approaches to solving the problem: 1. tackle the problem in a way that will give you long-term satisfaction according to your tastes and priorities by intelligent system building, or 2. use band aids now to tame a specific problem that will "help" this specific problem, but inevitably take the positive possibilities of your system.
Huh, you say?

1. Realize that the problem you are describing is a common (but not necessarily a deal breaker) problem with digital recording AND playback. This gets better all the time with new technologies and refinements of old, but compared to the sound of live strings, you will probably have to accept less-than-perfect at a price level anywhere near what you are talking about. There are many really good digital orchestral recordings as Almarg recently reminded me. But, there are an awful lot that exhibit the problem you are describing, and it won't matter what equipment you use for playback. However, the CD player can aggravate the problem already on the recording. So, that's where I would start. I really like the Ah! Tjoeb (Marantz
based) CD players in the budget level. It uses a tube output stage and sound fantastic with orchestral music. Always remember: any problem that is created by the source component will be there all the way to the end of the chain. You can mask it, but you will also mask information that you do want.

2. You can mask the problem. Some good suggestions above with cables and tweaks. Personally, I don't recommend taking that route. Your speakers and amp are solid, the CD player and pre, less so IMO. Tackle the problem in a way that will make you happy long term.

My two cents. Good luck.

I agree with the advice of those who suggest addressing the recording it self.If you find it is`nt the recording then I would next approach the AC power quality(this can make a significant difference) and audition some very good conditioners.If that does`nt solve the problem only then would I proceed to improving the quality of the CD player(source) and the preamp.As has been said already, you need a good recording reference as the first step.
regards,

If you are not satisfied with the sound you most likely need to change a component. A tube preamp is a good place to start. The question is what tube preamp will mate well with your system? The Quicksilver full function preamp has extremely low output impedance and will match with any amplifier. This also makes it less sensitive to cables. Trying to find recordings that sound good with your system doesn't make sense. It will shrink your CD collection to a hand full of recordings that you will listen to over and over. A power conditioner at this point would be nothing more than a band-aid.

Always follow the signal when auditioning a substitute component. So,that said,start with your source and continue downstream. My gut feeling is your CD player and your preamp are the culprit. Don't rule out better power cords(VH Audio power cords are very good for the money)and power conditioning as mentioned earlier. Power is everything! ICs and speaker cables would be the last resort. Get your components right first. BTW, No affiliation with VH Audio.There are a ton of good power cords to try.