Vac 200 IQ vs Ayon orthosII

Glad to hear your findings improved with the KT150s.  Keep us posted - I sadly have to part with my VAC due to personal finances.  It is truly a stunner - aesthetically and sonically.  At 100+ watts, I can't imagine a speaker that it cannot drive well.  Definitely seems like you're looking for the bass - the VAC plus the 150s will definitely give whatever you would need IMHO, plus a more beautiful midrange.    The other thing to consider is changing out the stock quad of the 6SN7 Tung Sol driver tubes to NOS tubes - some NOS Sylvania 6sn7 would show a much bigger improvement in bass and other characteristics than the KT88s to KT150s.   The 6sn7's are more sensitive to changes.  The opportunities are endless with the VAC and can fine tune it to your liking, as opposed to the PASS Labs.  Though PASS is still an excellent performer, not as flexible as the VAC.

Another option is the beautiful Aesthetix Atlas. They are hybrid. They may give you the extra punch with a beautiful midrange. They are NOT space heaters like some other Class A designs.

In response to Peter, I believe the discrepancy between the KT 88s and the KT 150s is likely related to musical style preference.  My understanding is the Kevin listens mostly to softer musical pieces which may favor the KT88s.  My taste is more toward more dynamic pieces, leaning heavily on Jazz fusion, rock, and blues.  The really amazing thing is the chameleon-like properties the VAC displays with these different tubes.

I found it surprising that some people still keep saying Ayon is from China. The fact is not entirely correct.

Ayon is an Austrian company.  It’s top line models (CD2/CD3/CD5/S3/S5/Triton/Orthos/Crossfire/Sparks/Sunrise, etc) are all made in Austria.

However, in its early days, the budget, low end entry-level models (Orion, and possibly CD1, may be Spirit I) were *assembled* in China with the same Austrian parts in trickled down designs.  Ayon pull the plug rather quickly, as QA issue and copyright infringement (remember Raysonic???) seem to be too big a baggage for Ayon to bear.

Not to digress too far.  I owned my share of VAC and Ayon equipments. VAC is just better in terms of warm and lushness, but relatively less reliable / less tolerant than Ayon.  I never had Ayon serviced nor it showing any temperament. A few VACs however, either died on me, or pick up weird ground noises / hums, or overheating tubes that need immediate action, or sound bad/weird if the power line isn't clean . Don’t get me wrong, when everything goes right, it’s hard to pick against VAC. Just make sure you have everything right to operate an VAC.

@peter_s  Kevin is absolutely right.   KT88 and KT120 both are OK if you want to hear harmonic sound. 

KT150 just sound different and I do not like it.