the preamplifier built in the ayon cd5 is great?

Thanks for the reassuring comments. I was very concerned that as I pushed the volume on the CD5 that I was going to badly overdrive the amplifier. It does seem quite linear rather than front loaded. At low volumes, you don't get much bump from the CD5 volume control. As you get to about -40 though, it really starts to take off.

Fair bit of difference between the Zu and Aliante? No. HUGE difference. The Aliantes, you have to push them. The Zu's don't require a big shove, but they really, really start to sing when you open them up big time. The imaging and soundstage just explode as you push the volume on them. The Aliantes, they just kind of get louder.

I think what you experienced with the VAC, I'm getting a similar thing with the EAR. I'm sure you're familiar with that unit. Does it stack up similarly to the VAC?

Not so sure about the need for a high powered amp with the CD5. It really cranks with the 30 wpc Mastersound and the Essence speakers. Less efficient speakers, yes, maybe. But I notice essentially zero difference between the Mastersound and the Rowland 102 with regards to dynamics. The Mastersound has tremendous headroom that the Rowland doesn't seem to match, and with a six ohm load, that's a 150 wpc amplifier.

I read a thread recently in the amp/preamp forum about solid state amps increasing their power output as the speaker load decreases. Makes sense. But the author laid something out with tube amps that was the polar opposite of that- something akin to tube amps increasing their output as resistance INCREASES. I didn't touch that one, since I don't understand the concept. Is that a true concept?

How is the heat issue and lifespan of the 8 tubes in the CD-5 ?

Tosses a fair amount of heat. Not like an amp, but it definitely gets warm over the vents. Ayon claims the tube life is 5000-10,000 hours.

Afc, the EAR components are also very good sonically, from what I have heard at shows. I have not compared them in my room.

Here are some articles which discuss basic differences between SS and Tube amps:

http://www.soundstage.com/gettingtechnical/gettingtechnical200405.htm

The Second site has a lot to do with guitar amps,etc. but I found the answer to #2 to be clear:

http://aga.rru.com/FAQs/technical.html#pwrvsvol

Regarding the heat from tubes, I would not put the CD-5 into a closed shelving unit, but it does not throw so much heat that a room would be adversely influenced.

Doug, I just ordered a CD-5s much on the strength of your review (and the way people respect your opinion)and then reading everything else I could find. The fun part is, as an antidote to getting too pumped by a review, I decided to reread reviews of my speakers that I dearly love. When I pulled the 2007 review of My Von Schweikert VR4SR's, lo and behold, you wrote that review as well. And having lived with this speaker for years now, I can say that everything you said about them was spot on correct. Gives me a lot of faith in your CD 5 review.
Joe