Just replaced my Heresies with Cornwalls. I own several amplifiers and decided to try a few to see which I preferred with the Cornwalls. And it seemed to me it did make more of a difference when listening to the Cornwalls as opposed to the Heresies. I attribute this to the Cornwalls having a higher sensitivity and lower bass response.
Here is what I found:
Higher power + newer amplifier = worse performance
Lower power + older amplifier = better performance
The best sound, to me, came from my collection of 1967-1975 vintage solid-state amps.
Tubes versus solid state: my Fisher X101D tube amp sounded great on acoustic material, but as soon as I put on some Jimi Hendrix, something was lacking. The vintage solid states just took it up a notch and better than new solid state.
the worse the sound. Conversely, the lower the power, the better the sound. It takes less power to drive the Cornwalls and those first few watts are what count.
The newer the amplifier, the worse the sound. Stated differently, the older the amplifier the better the sound.