Best upgradable system components for under $6K

"You might consider active speakers since at least one of the components (the amp) comes along for the ride.
Bob_reynolds (System | Threads | Answers | This Thread)"

Given the OP's budget, he probably won't be able to get both pieces at once. The amp is the more expensive piece so it would probably be best to get the big purchase out of the way. Also, the OP's current speakers would probably benefit a great deal the extra power. I don't think had enough power to drive them to potential.

"03-26-15: Onhwy61
A well designed active system will out perform an equivalent passive system every time. Actives allow for better implementation of crossovers and improved synergy between the amp and the crossover/drivers. Examples are JBL, ATC, Pass and Gradient."

The amp and the speakers still have to be designed as well as the separates in order for that to be true. And that's usually not the case. Can you show me 1 active speaker, at any price, that has a fully balanced, 0 feedback amp that sounds as good as an Ayre V-5, in the same box as a time and phase correct speaker that performs on par with a Vandersteen Trio? An active speaker like that doesn't exist.

"03-26-15: Onhwy61
The whole point of an active speaker is that it functions as a single, integrated component. It is more than an amp connected to a driver. Take a look at the Linkwitz floorstander. It is an active loudspeaker system designed to function optimally in a real room."

I understand where you are going with that, but just because a active speaker is well designed, doesn't automatically make it the best choice. You're not taking into account the sound quality of an active speaker. Using the Ayre/Vandersteen example again, how would you find an active speaker that has the same qualities as that combo? Both pieces have a very unique sound. I've never heard another amp, regardless of cost or brand, that has the same sonic qualities as the Ayre V-5. Same thing with Vandersteen. No active speaker that I know of is time and phase correct. So, if you like that combo, you won't be able to duplicate the sound with an active speaker. You'll need to buy the separates. There's just no other way around it. Maybe if Ayre and Vandersteen worked on building an active speaker together they could make it sound like the separates. But that would be it. It won't happen any other way.

"My ultimate goal is to one day be driving a pair of Acoustic Zen Crescendo or Vandersteen Quattro speakers. A 200wpc + consideration would be preferred but I’m flexible on that too lol."

If you want to do this right, you should plan the system out now, even if you can't afford everything all at once. The Vandersteen as a possible choice caught my eye because its my favorite speaker and I have some experience with them. For solid state, I feel Ayre is the best match for Vandersteen. You may want to consider an Ayre V-5, and then maybe a K-5 preamp after that. But just getting a V-5 now and using your NAD as a preamp, you won't recognize your system. You'll think you got new speakers, as well. That's how much of a difference it will make. But you should do some listening first, to see if you like the combo.

"You might consider active speakers since at least one of the components (the amp) comes along for the ride.
Bob_reynolds (System | Threads | Answers | This Thread)"

Going with active speakers would almost certainly be a huge downgrade in sound quality. There's just no way around it. The OP is considering a Ayre/Vandersteen combo. What kind of amp in a powered speaker would be the equal of an Ayre V-5? No active speaker that I know of, at any price, has an amp that can even comes close to it. When you ask the question, who is the best designer of solid state amps and preamps Charles Hanson is going to be at the very top of the list. There's only a small handful of designers in the world that are in his league. Now look at the speaker. What active speaker is on par with a pair of Trio's? Again, there isn't one. Like Hanson with Ayre, Vandersteen is one of the worlds best speaker designers. Vandersteen speakers are all time and phase correct. Its not easy to design a speaker that way and I'm pretty sure there's only 2 companies left that build speakers this way. Vandersteen and Green Mountain Audio. Thiel died and the company is no longer making speakers and Meadowlark went out of business a few years back. You really can't substitute a Vandersteen with any other speaker. Powered speakers are going to come up way short in comparison to what the OP is considering.

"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.

"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.