Sounds like the OPT (output transformers) are rolling off the bass and treble. A common problem with tube amps - both single-end and push-pull. Good big iron is expensive! Witness the Carver 275 amp with the small crappy transformers! For its high price a waste of money! I suggest getting a way more powerful amp - tube or transistor. A Crown XLS 1002 (200 wpc) would be a good match for the Paradigms. There is one for sale now on eBay for about $400.
melody 2a3 mono amps
i have 2x melody 2a3 amps plugged into sonic frontiers sfl2 pre amp both are tubed. speakers i run are paradigm studio100 ref with a sensativity 94. plenty of power at 18 watts from melody's...problem is there is very little bass. not enough to make brass sound like brass the sound stage is way behind speakers(very good)cymbals sound like steel. doesnt ring like brass and so on .should i change speakers or amps or..........