The lighter amplifiers I have listened to are okay to great with efficient speaker loads at lower power levels. but, give them a difficult load or inefficient speakers and we have a problem. I prefer to not have to change my amps when I change speakers. Just me. When I move towards more efficient speakers, they better sound as good or better than the ones I now have and work well with my current amps. I can't see myself replacing all my equipment at one time. For me, I upgrade when I feel something is better than what I have sonically, I can afford it and I feel it is time for that upgrade. I am very happy with my system and amps although I have heard really nice amps, such as the Boulder amps and the Audio Research Amps, etc (there are more). But, jaw dropping differences? Well, no. Not jaw dropping. for me to upgrade to better amps, I would have to spend tons of money that I really don't think it is wise to spend right now. But, the Audio Research Reference 250 amps are really nice. I like the sound. So are the Reference 750 amps. It is also a long term issue with me for equipment. I know people that listen/demo once or twice and purchase, only to find out later that they should have listed/demo'd more before buying and they are really not happy with their new stuff over the older stuff. My favorite store in San Diego sells Audio Research, Krell, Boulder and many other amps tube and solid state. And they would let me take one home for a week or so to demo in my system before purchasing. 300 to 400 pounds would be a problem for me using my car, but it would be fun to find out.
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