The DNA-125 will drive most difficult, low-impedance speakers very well in normal-size rooms. A friend of mine uses the DNA-125 to drive his Apogee Stage speakers and it does a fine job. It will also do a good job of driving the Kappas, although it may be argued that the DNA-225 would be a better choice if the room is very large. You are correct, of course, that the DNA-2 is "more capable." It is a much larger, more expensive amp (out of production for several years, now) that will deliver 300W per ch into 8 Ohms.
Best regards,
Steve McCormack
www.SMcAudio.com
Best regards,
Steve McCormack
www.SMcAudio.com