Wow - this is a difficult comparison!
I just purchased a pair of Vandie 3A Sigs from a fellow member here a couple of weeks ago. While I have not heard the Cornwalls nor any other Klipsch model in quite some time, I have to assume that their design philosophy and engineering have not gone into any sort of radical departure since I owned a pair of Epic CF-3’s and a pair of KG4’s. Highly efficient, horn loaded compression tweeters...
The Cornwalls have an efficiency rating of 102db, the Vandies are 87db. The Vandies go down to 26hz, the Klipsch 34hz. You could pretty much drive the Cornwalls with a table radio, the Vandies...need a little more power on tap. Your amp @100 watts per channel is sufficient for either methinks, but will probably be less stressed with the Cornwalls if you listen at high levels. I don’t. While my choice of amps has usually been around 150 watts for the past few years, that’s more because I found them affordable at a particular moment in time as opposed to me needing more power to drive a particular pair of speakers.
Anyway...
It’s an educated guess on my part that the Cornwalls will definitely sound “brighter” than the Vandies simply due to the tweeters. Methinks they will also be “punchier” throughout. Having moved through Thiel and Magnepan models over the last few years - both reputed by many to be “bright” speakers - I can offer that the Vandies definitely are more reserved in the highs.
The Vandies do require bi-wiring and have smaller than the current standard size spade connects on the rear. I use anti-cables for them, which has an option spade to fit the 3A Sigs perfectly. They’re not too expensive, either. There’s also a dial attenuator on the rear to tweak the treble response up or down if you find the flat setting too little or too much. Also they come with very substantial, HEAVY metal stands. You can adjust their tilt ever so slightly as well once they’re attached. The stands are spiked so be careful of your flooring - assembled these puppies weigh about 90 pounds apiece.
Pricewise, unless the inter-web is misleading me, has the Cornwall III’s around $2200 apiece new. The averaged price for the 3A Sigs, used, is around that for a pair according to the A’gon Bluebook. I picked my pair up for appreciably less than that somewhat locally, requiring an enjoyable four hour round trip to get ‘em. They’re no longer manufactured but can still be serviced by Vandersteen should the need arise. I’m replacing the socks on mine which cost about $150. The folks at Vandersteen replied to my inquiry about doing so quickly and eagerly, even thanking me for purchasing them used. Imagine that.
I continue to think that Klipsch makes excellent speakers. My reason for moving away was what I perceived to be the harsh treble response. Very recently I was thinking about returning to a lower power amp along with more efficient loudspeakers. I researched the Epic CF-3’s that I had around 22 years ago and found a pair advertised for $800 - the same price that I wound up selling them for around 15 years ago.
Klipsch, Thiel, and Maggie fans are a rather unique collection of people accustomed to hearing widely varying opinions on everything about them. I’m digging the Vandies because I found my Maggie 1.7i’s to prove bothersome simply due to their physicality. I had to rearrange too much to get them comfortable in my living room. Love ‘em, BUT...
