Yes I have heard both. A couple of models from Volti and many Tannoy over the years. Iif you like horns then the Volti sound like a good horn speaker. Better than Klipsch but still a horn with all the advantages and warts of this type of design.
I really dont like speakers with the general design characteristics of Tannoys. To me a very odd sound. Hard to place with a kind of weird presence that is hard to get to go away. I can embrace horn sound in a few areas, I cant embrace much if anything about the larger models from Tannnoy. Many of the head people at Tannoy left and started another company of similar design out of Scotland I believe.
I havent talked with anyone that prefers the Tannoys to the offerings of this new company which I think might be Fyne Audio.