Best upgradable system components for under $6K

"Would it be a problem to match a Class D amp with the Class B amp that is built into the Vandy Quatro's?"

It will work with no problems, but its not an optimal match for Vandersteen. If you find that you want to build a system around class D amps, You would probably be happier with a different speaker. Probably the best way to pick a system is to start with a must have, and then build around that. So, for example, class D is your must have, build a system around that feature. Everyone’s different. I know many people that focus on vintage, others that like horns, for me personally I go for sound quality. Just start with the most important area, and go from there.

Great points!

Roscoeiii: what is a DSP? How does it replace a pre-amp and a DAC? That sounds like a very interesting option...

Zd: that makes a lot of sense. I think the speakers will be my main focus. So with that in mind do I need to make sure the amp is a class B (if I do go with the Quatros to match the built in amp)? Sorry I might be reading too much into this. Also what has been he best DAC that you have seen to work with Vandersteen in your opinion?

DSP stands for Digital Signal Processing. Google reviews of DEQX to get an idea of their products' functionality. Most recently there was a review in Stereophile. And there is a thread here, something along the lines of "Is DEQX a game changer?"

"Zd: that makes a lot of sense. I think the speakers will be my main focus. So with that in mind do I need to make sure the amp is a class B (if I do go with the Quatros to match the built in amp)?"

If you want to get the most out of the Vandersteen's, there is an overall strategy that seems to work best. Vandersteen speakers are designed to be time and phase correct. Where people sometimes go wrong is when they just consider the speakers themselves, and not the whole system. In order to be time and phase correct, you need to start at the source. The most accepted way to achieve this is to use electronics that are fully balanced and use 0 negative feedback. You definitely don't want to use any type of EQ or signal processing, analog or digital. For example, if you put an EQ in your system, any adjustments you make with it, will alter phase on whatever frequency you are changing. The signal then goes on through the other components, and you end up sending the speakers a signal that already has the phase altered.

So if you want to look at some equipment that will work best with Vandersteen, I would start with Ayre for solid state. All of their products are designed in a way that is the best possible fit for Vandersteen. You can look at other brands, as well. For a source, I use Wadia CD players. They're also fully balanced, 0 feedback components. For tubes, I like Aesthetix and BAT. ARC and Pass also work well. But before you buy anything, you are going to have to demo any of these products first. They're expensive, highly resolving and a mistake will not be cheap.

Zd: thanks for the recommendations I will definitely audition them. What do you recommend as far as DACs that would fit well with the Vandys? Does the Ayre DAC fit that bill? Based on what I am hearing I think I will need to raise my budget.