Wayne Parham Messages: 18789 Registered: January 2001
Illuminati (33rd Degree)
The full part number of the current production DX-25 tweeter is DX25TG-09/04, which as you've said replaced the Vifa DX25TG05-04. They're virtually identical, essentially a copy made at a different manufacturing plant.
The towers do provide a healthy dose of midbass "punch" and also more deep bass than you would probably expect from a 10" midwoofer. It's a very satisfying loudspeaker.
I've been very happy with solid-state and tube amps. I've personally run my two π towers with a 50 watt single-ended FET, a chip amp, a modern Harman-Kardon receiver, a single-ended 10 watt tube amp and an ultra-linear 10 watt push-pull tube amp. The towers present a benign impedance load and are fairly efficient so they can be run with pretty much any amp.