$10k DAC in a 3k system?

Speaker should be first priority, Pre-amp- & Amplifier as second. . However if you feel it can be justified by all means go for it.

An alternative choice would be buying a lower end dac which can outperform others many times its price. Some of the recommendation already made are very good choice.

If I was you and had 10K to Splash. Id be looking at a second-hand but well looked after speaker on the market.

What Charles Said:

Performance and cost isn't always a linear relationship.

This is very very true and something which one learns from years of experience.

I can only speak from my experience. I made many, many changes over the years. In my experience, changing speakers and the source has had the most impact on my system. I recently changed my music server. It's so hard to describe the differences without individuals thinking that I'm exaggerating or lying. I don't know if it's because the new component has synergy with the rest of the components, the music server that it replaced was so bad, or the new music server is just that good. The only way to find out if it's worth spending 1K or 10K on a DAC is to get a home trial...let your ears decide.  

Dragon_vibe,
Yes, my comments were precisely based on listening experiences of many different audio systems over the years. I must respectfully disagree with shadome’s post. I don’t believe that you can accurately apply a rigid cost ratio amongst audio components when constructing a system, far too many variables and exceptions to account for.

Speakers are often said to be the "most" important link in the audio chain and thus require the greatest expenditure. Yes they’re important but so is "every" component link in the audio chain. The weakest link will by default be the bottleneck.

You can develop an excellent sounding system with the speakers being less expensive than the source, preamplifier or power amplifier. The truth is that there are multiple methods to allocate money toward assembly of an audio system that results in terrific sound quality.

My contention is you have to actually listen to components/speakers rather than make determinations based on solely preconceived price points and ratios. I do believe that generally speaking  quality increases with cost, however High End audio has numerous exceptions to this rule. Successful synergy isn't exclusively tied to spending ever more money. 
Charles