Vac 200 IQ vs Ayon orthosII

Vandersteen quattros were used.  I was told they are a good pairing with the Vacs. For the Beck and Sanborn album and Keith Jarrett Koln concert the sound was good.  It was the intro to Michael Jackson's Billy Jean that really lacked the umph in a big way with the VACs compared with the SS amps.   Thanks for your ongoing interest. I'm making another road trip in few weeks to tweek the combo.

orthomead, what speaker tab and output tubes used in the demo?  Try 1-2 or 2-4 ohm tabs?  Also roll KT150 if possible.

I suggest including ARC REF250SE to your list of amps.  There are many Agon members driving their Vandersteen's with ARC ... an excellent match.

Jafant makes a very good point about particular music genre preferences. Electronica , Hip hop, pop and rock, actually any music emphasizing electronic bass may with certain speakers be better served with high current transistor amplifiers.

Ideally a comparison of the Ayon Ortho, ARC REF 250 and the big Pass Labs amplifier driving the Vandersteen Quattro would effectively sort this out. I’m generally speaking a tube guy but in some circumstances solid state is the better suited option. Sometimes SS amps with low output impedance (thus higher damping factor) are the solution. This can be manipulated by altering the amount of NFB (negative feedback) in the circuit. Increasing the level of NFB  will decrease the output impedance of the amplifier. 
Charles

I'm not sure what tabs were used but the stock KT 88's were in place.  I did discuss a trial with KT 150's.  I'll be back in a few weeks and ask the dealer to roll the 150's.  Tomorrow I'm auditioning  a local ARC GS 150 with a vinyl set up so I should have a good comparison using my vinyl standards.  Unfortunately I wont have the Vandys at this dealership.  Jafant must have sensed my tendencies-love guitar.  The SS killed Al Dimeola's Alien chase on Arabian desert as well as the finger style Silent story in her eyes. Again, many thanks to all for joining me on this journey.