Here is the Stereophile test report, which includes some measurements. I heard this speaker many years ago, and concur with the reviewer's conclusions - it's a pretty good speaker. The biggest difference between these and newer speakers is that, IMO, the quality of modern tweeters has come a long, long way since the Hales were designed, so while the Hales probably sound good, a lot of more recent speakers will sound better, I think. Assuming you can get these for a very reasonable price, like perhaps $1000 for the pair, they are probably worth it.